I've got a pair of new doors and am ready to start prepping them for primer/paint and was wondering what to do about this coating they come with. It seems pretty tough, but I don't know if it's safe to leave it (most of it at least) after cleaning, scuffing and cleaning again before I shoot it with some filler primer. I'd rather not have to strip both doors comletely if I don't need to. When I replaced the left rear quarter panel a few years back it had the same coating and I stripped it inside and out, but I was doing a lot of cutting and welding on it and didn't want to worry about having paint in the way. I got all the panels and doors from Mid America Direct, and they look to be made in Mexico.