[DanEC]

Unlike older Corvettes, replica fiberglass bodies seem to have remarkably good quality for the most part and to be free of developing stress cracks. From building my own and watching other build threads there are a number of steps necessary in the surface preparation to resolve small air bubbles in the gel coat and to dress out mold lines/seams. And then any fiberglass body is going to need a lot of blocking and some filler to get it really straight but once done properly they seem to hold up really well. ERA has been building their Cobra replicas since 1980 and I think they still have yet to hear of a stress crack developing in one.

They can be subject to rocks and debris being thrown up to the inside fender surface and creating star cracks. Some of the manufacturers put coremat in those areas as extra protection. On others, buiders have done a variety of things to protect those areas - rubber sheathing, bed liner, heavy undercoating, coremat, etc.