I used a 2 part foam before I touched greatstuff, however I didn't order the second/larger package, and needed some more. I used some spray foam only after I used up my 2 part foam.Only thing I would have changed is your use of GreatStuff.I hate that stuff, there are much better products that could have been used instead.
I never tought about it, but I don't think I'll even bother trying seeing how much of a pain it'd be to do that.Since your fiberglassing your whole trunk, you should try to fiberglass the trunk lid. This may help minimize the amount of sound that exits the vehicle.
I realized that, but I thought I'd try something new seeing that it's be pretty hard to glass vertically, just try something different, the only thing is, the fleece was kinda thick and not very stretchy, However fiberglass is stronger curved than flat.Just curious as to why you used fleece as the base layer over the metal of the car? You went to the trouble of laying down foil and taping everything, why not just lay a few layers of mat right on that. No wrinkles and gets stronger with less resin and less hassle. Too late now but something to think about if you go after a project like this again. Fleece is best use stretched over a framework to make smooth curves not laid against and existing surface.