I have seen entire body kits held in place by double sided tape. Don't confuse it with the cheap stuff for hanging pictures and such, I mean the auto grade ( I think it's 3M or something) heavy duty tape. I wouldn't trust the tape entirely ( just my opinion) I would also add some screws for sure. The bumpers require bolt mounting points but I was referring to lips and side skirts to be exact. Unless you have fiberglass experience, I'm not sure I would glass them on. We've done fiberglass for 10 years and I'm still leary about molding parts to cars other than scoops. Just my 2 cents.