All cars got the wheelwells done, all rear qtrs have the heavy sound deadening, some race car packages may not. Undercoat is a separate code, j55 I think, can't remember the delete code if there is one. The factory floorpan undercoating is distinct, and easy to tell from dealer or ziebart applied, kinda like restamped blocks, fender tags, original black brackets, you just know it when you see it after looking at enough cars. I caution guys to at least undercoat the insides of the front fenders, and do it heavy, rock dings from inside out will show in your mirror straight paint if you don't.