Can't speak to the 355 rear bumper, but I have the front bumper. Its thick, well laid fiberglass, but there are some issues with the shape. Looks like a well made production piece of a not so well made mold.
Is it the one I am putting on Johns car? it was Deans prototype. Far as installing it so far it is roughed in and the plastic egg crate cant be used. there are a few little issues too but nothing major with the area by the side molding/ side marker lights. I had to notch out a bit but it should be self explanatory installing. http://www.fiero.nl/forum/F.../HTML/092359-12.html