Treated mine to a thorough rub-down and underseal. I’m ancient and lazy, so I paid a reputable garage (in Oldham) to do it for me - Undersealing Service in Oldham - Duke Street Garage
Cost me £850 + VAT, and they had the car for a full week. They also sent me 40 photos of the work (before, during and after). Here’s a couple of pics.
Nick