I am installing a fiberglass ground effects kit on a coworkers 2001 Honda and have ran into some problems. First off... the kit he order was a piece of crap and now I am having problems installing it. I am working on the rear bumper right now. The body lines didn't line up good so we decided to mold it in to the quarters. After making a few cuts and trims here and there it looks pretty good, BUT after I primed it I have been having problems with it. I sanded the whole bumper down with 80 grit before I primed but there are some places where the primer is just peeling off. And after I primed I also noticed some places where the fiberglass had air bubbles and it is bubbling the primer. I took a razor and cut the places out that bubbled up. It seems like the more I sand it the more bubbles pop up. I added some short hair fiberglass to the places that I cut out and re-primed the bumper and noticed more places bubbling so I cut those out and am going to try and repair them tomorrow. My question... would finishing putty work in these places or does it need to be fiberglass? And what would cause the primer to not stick to the primer that came on the pieces? There was a couple places that I tried to sand the primer off with my air grinder and ended up going through the fiberglass. I used Evercoat lacquer primer on the pieces, maybe this had an effect on the primer that came on them.