Well, I know the 3M tape holds pretty danged well - I've got the SHR honeycomb trunk insert, and that's all that's holding it on.
My worry would be about a part that is in the front - battered by air, changing wind conditions, junk on the roads (even when you try to dodge), etc. I still have the bolts/nuts/washers left over from my Astra-Hammond kit, and was going to see if I could re-use them to shore-up the install anyways. That way, it's even more secure, and I don't have spare parts collecting dust. Lol.
2009 G.O. GT, Spoiler delete, JLT-style CAI, Bama 93 Oct tune, Quantum Motorsports brake duct cooling kit, SHR quarter-window louvers, MGW short-throw shifter, Steeda UDPs, JLT oil separator, FRPP FR500s mufflers, MSD coil-on-plugs, FRPP 1.5' drop shocks/struts/springs, FRPP sway bars, Michelin Pilot Sport A/S Plus tires, stock 3.31 gears