All the above. Tape, sheet metal screws, silicone. The material is called corrugated plastic. Made just like cardboard, but plastic instead of paper...
Richard White
2011 F150 Ecoboost SCREW 145" 4x4
Firestone Ride-Rite Air Springs/Air Lift Wireless Controller
2006 Sportsmen by KZ 2604P (30')
Hensley Arrow