These cars are finished the same way boats are. A fellow NJRC Club Member who has a VW based TD gave us all a tip…keep the finish in shape using products made for boats. You should see his bright red MGTD. It’s 25 yer old gel-coat and shines like a $10,000 paint job.
3M makes a bunch of gel-coat finish products that are available at any decent boat supply place. In the NJ Shore area there are many boat supply vendors, private and chain. I go to a West Marine that is only a mile away from my house.
I’ve used all of these 3M products from gel-coat to clear plastic cleaner and conditioner for the rear window in the convertible top.
THEY WORK BETTER THAN ANY CAR PRODUCTS.
He also told us to use boat hardware on our kit cars…better quality chrome and most parts made from stainless steel. i.e. badge bars are made from boat rails.