Mk4 Mirror Cap Replacement

I’m about to take ownership of an ND and I want to change the mirror caps (from white to black). I have the replacement caps from MX5Parts but there aren’t any instructions, so a search of Youtube has produced a clip of a man wrestling the cap off, with some alarming crunchy sound effects!

So, has anybody completed this manoeuvre please, and is it just a matter of pulling and pushing? There are a lot of plastic projections on the inside of the caps which appear to be easy to damage 

Dare I say it, why not try asking your local main dealer.

Thanks Mal - yes, I think that it will probably come to that, but if somebody persuades me that it’s not as tricky as it looks, I’d have a go. I haven’t got a ‘relationship’ with my local dealer yet as I’m buying the car from somewhere else, but I do intend to use the local for servicing etc. so perhaps this could be my intro.