What ever you do, careful about flailing your arms around the inside of the hard top. The texture on the ceiling can rip skin off!
If the fender flares are painted, that will be easy to deal with. If they are unpainted and very faded, in general most dressings applied will not last very long. The only way to fix faded grey flares is to paint them or
take a torch to them. If the customer is happy with general plastic/tire dressings then I personally would let them understand the dressing will fade as well.
