Good point Ed, I never thought about the gas attacking the silicon, it will break it down eventually and could cause a leak. Might be better off pulling the intake and get new gaskets and startt over. I like to use spray trim adhesives for most all my gaskets, it hold them in place and doesn't leave any residue. which brings to mind people that used 3M 8001 weather strip adhesive A.K.A. ( gorilla snot ) that yellow crap was a nightmare to clean off of gaskets surfaces. Oh how I dont miss those days working in the shops and dealerships.
Cp