If you bought a “new” set of clocks youd have your answer.
Personaly, keep original millage.
Has to be road legal, yes. The MOT bypasses lots of MSA regs 
Definately need a connected speedo, and there’s no sense replacing whats there as it works fine… is my conclusion. Keeping the old one satisfies everyone (scrutineers, MOT man) and using a GPS unit does me favours as the reading isn’t affected by the final drive, although the odo. will be, and it frees cluster space for other important stuff like AFR, EGT’s (when I run FI later), etc. etc. 
The only reason anyone would want to reset the miles is because they are trying to increase the value of that vehicle, making it look like it has a load less stress on it. It’s dishonest. Period.
Would you like it if you bought that car, or any car, and later found that it had a 150k on the clock?..of course not, you would be livid…you could zero the clock, and provide them with all the paperwork that proves it’s milage to that point…but i don’t think you are.
There is no excuse for anyone “adjusting” the clock. It’s not just the parts you are replacing that have done no miles, it’s everything else. I admire you for posting this thread, and the fact you don’t appear to care…either way…but I would never buy from you, and would suggest that no one else does, if you are prepared to cut corners over a speedo reading, then where else are you not being honest/doing a decent job making this a safe honest rebuild?
Do the right thing, leave as is, and sell it on being 100 % honest. That person may well come back and buy another in the future, if you cheat they will come back and give you a bloody nose.
I am proud of the miles any car i have owned has done, if it is well maintained, serviced, with new parts on it, I would be more inclined to buy it, than a car with “no History”…anycar like that should be walked away from…there are plenty of cars that are clean, why would anyone buy a car that may be dodgy?
I hope you sleep well…
Easy, tiger. If I were rebuilding a road car, I would agree for the most part. Ditto if I were building a car for ANYONE else. But at the end of the day, I’m building neither. This is a competition car, just so you’re aware as I suspect you missed that point, and she’s only road legal (just) in so much as I qualify for the series, can run components/the build in and share the experience with my little ones.
It’s looking like a moot point right now as a chat with my chap at SPA design earlier has thrown up an 80mm tacho with built in, configurable, electronic speedo…
I agree with Rich M, there’s no need to clock it ! as I guess you have all the records receipts etc for all the work you’ve undertaken to pass on when you sell and there are always going to be older parts on the car that have done the true millage.
this is becoming a fascinating and controversial topic, and there’s a lot of emotion here.
i can understand the fears of some that its all an underhand business to pass off a car as being much less used than it really is - the use of the word ‘clocking’ (the slang term for mileage fraud of course) is surprising me also; it’s not a question of cheating for profit in the slightest! More one of exploring people’s views as to what point one life of something ends and another begins.
I’m not enjoying having the implication of my question being criminally motivated that’s for sure.
I’m not much for what a lot of my associates call ‘moderns’ and in the world I live in, it’s mainly vintage and classics, road and race cars, and it’s very much a case of provenance, use, and supporting documents other than MOT’s going back to X, insurance databases and the like. Don’t get me wrong, I’m all for these things, and definitely don’t buy a stolen vehicle, or a cat B/C car unless it suits its intended use, but I’ll always use the condition as my primary decision maker, and that condition will differ depending on what I’m looking at. Personally, if I’m looking at any car more than 20 years old, with 7+ owners on the logbook, the vehicle itself and its surroundings will tell you so much more than an odometer anyway.
Oh, and to my critics ( 
) if a buyer approached me, god forbid I ever have to part with her, AND I’d replaced the speedo, AND they’d gone through the currently thirty two parts invoices, AND they’d been through the build file, AND they’d misread the advert stating ‘seasoned hill climb and sprit car for sale’; all of which they’d have to go through first… And they cut up rough because the odometer reading didn’t tally from the original date of sale, then frankly, that person is an idiot, I would be recklessly irresponsible to sell it to them, and I would refuse the sale!
B
Hi Ben, yep, I understand you’re only doing it for yourself, it’s your car, you rebuilt it, should you now zero it? No implication of dishonesty in any way but when I rebuilt every item nut bolt and paint of my old Triumph bonny I didn’t dream of resetting the speedo. It is what it is. Crikey it may have been wrong already when I got it but at least I didn’t change any history. I do agree as well that anyone buying an old car would/should always buy on condition and assume the mileage is probably wrong. How many cars are there for sale with “69,000 miles” ha ha that seems the clockers favourite. Yours set to zero would be very honest indeed because it would be obvious but it would lose something still and I can see by your other car you know that 
Hi Rich, understood. And definitely on a resto it’s all about preservation.
Did you see my post about SPA? I think I’m going to go that route and have a custom panel, but I didn’t query if the SPA tacho has an odo. function… Oops! Best check if there’s any knock-ons with that and the MOT! So much to do!!
Cheers for your input, much appreciated
TIME FOR A LAUGH
Two guys in a pub were discussing their cars. One said he had problems selling his because it had 200,000 miles on the clock. His mate tells him not to worry, as he knows a backstreet garage which would turn the milometer back substantially for a few quid. A week later he asks his pal if he had now sold his car after the shady deal had been done. ‘‘Naw,’’ says his mate. ‘‘Why should I? It only has 30,000 miles on it.’’
^ good call!
and the non-nationalist version too 
What a hornets nest is brewing. I do enjoy a good bit of banter.
If Bens car is going to be 95% track orientated and a full set of digital dials are going in, then i don’t see the problem. A race car is a race car and spec is king when selling. Also If everthing is documented and pointed out to the customer if it ever is sold then that is fine also. The dishonesty come from people who do not pass on information they know to be wrong, or own up to faults they know a vehicle has.
Every day I have members of the public trying to palm off cars they plainly know have faults as part exchaanges . Easy 1 in 10 have hidden histories, another 10% clear engine management faults just before bringing them in. Most will never own up to any faults if you ask them. etc etc.
If a person is honest and informs you of everthing you need to know then great. It’s when things are hidden then you cannot make a good and informed decision about a purchase.
Did you all know. It is now Illegal for a dealer to sell a vehicle and withold any adverse information that affects its value. ie major accidents,mileage discrepancy, imports, finance etc.
There is little you can do if a private seller witholds information from you.
So much venom??
A competition car has a much harder life. The miles mean FA really. Look at the top gear cars, take out the cage and seats and sell it as low mileage??
Ben do what pleases you, Personally I would reset it as it starting a new life 
It’s your car so do what ever you want with it. If you’re keeping it so what ? Just make sure you have a complete record of what you have done to the car ( and speedo ) which I’m sure you will have so you can pass it on to the next owner. They could always reset the speedo if the wish.
Chris.
If you’re on 151K now and are doing a complete rebuild you might even get to beat my 231,800 and rising. I’m looking for 240K + before the rust eats it entirely. Any more will be a bonus.
Having now got all the facts, having read Benf’s rebuild thread, and finding it a really great story, I agree that on reflection I may have been a wee bit harsh in my previous post. This looks to be a great rebuild for the track. I shall follow the rest of it with interest. But, i still feel that the milage should remain as was, as why change such history as displayed in all those photo’s?
I even go further and suggest that it’s a shame I don’t live closer, and could have offered to help in any way, if for nothing other than learning the knowledge offered for the rebuild we are watching…enjoy your car, and do whatever you like to it…cheers
thanks Watchnut, both for your reflection and input, and for your offer of help
keep your fingers crossed I don’t park her in the trees first time out!!
cheers, B