Re: colour fadedN
As above start with super resin polish on a damp foam applicator pad use a pea size blob on a 1foot square area at a time and work it in well
If that doesn't work you could try auto glyms paint renovator then srp
As for the sealing I'd go with some auto glum extra gloss protection spread thinly and leave for one hour to cure before removing
Keep all these products off any black textured plastic automotive masking tape to mask it off is a good idea