Build up of paint causes shelling or chipping I say Strip it . The use of toluene paint thinner will blister the clear coat after a few seconds, and then can be scraped off with razor blade , if you don't get it the first time do it again you will definitely feel the paint getting soft . It is less caustic than paint remover which will work , but might melt the plastic . Then take a heat gun to the decal or use the "Wonder Wheel" as seen on TV to remove the decal. Remove any residue with W-D 40 and wipe with denatured alcohol. I would use a "Two Part" catalyzed polyurethane and retarder with recommended thinner most likely methyl ethyl ketone , but not too thin this paint is made for .0003 mils a coat , , wet coats that are applied with a HVLP (High volume low pressure) sprayer which works well with smaller compressors and these paints don't need a clear coat but they must be mixed well and strained . If you live by a Marina these coating are used for boats and bath tubs and even tile the other stuff can be got at lowes. The mix that worked for me was 2 part base to 1 part catalyst and thinned 25% by volume not weight . paint takes hours to dry and 3 days to cure but it cures long after that.