VHB is tape made by 3M, it comes in several widths, it is double sided tape the steel and aluminum must be very clean, once stuck you have to grind it off unless you get very lucky with a heat gun. Very expensive, but the end result is a clean sided rig with no chance for water to seep past the rivet holes.
Stop buy a semi trailer repair shop, they can show you and price it for you.
link:
http://solutions.3m.com/wps/portal/3...apes/VHB-Tape/
-blizz