Your replacement panels should be as close as possible to what is in the truck now. Using a different thickness just because it was convenient at Home Depot will normally add to any weld distortion as the different thicknesses will react differently to the heat. Check actual thickness of what you're working with and see if any local machine shops or metal distributors have what you need. Keep in mind there is a tolerance in thicknesses, so when shopping I also tend to measure the thickness of the new stuff to make sure it's close. I like having the panel thicknesses within a few thousandths of the original metal, the closer the better.
If you don't have good luck in finding anything, I do have quite a few sheets of 19 ga AKDQ here, I could cut it into just under 12 x 24 pieces and load the whole thing in a flat rate game board box, as shown here:
http://www.jalopyjournal.com/forum/...october-2015.995188/page-3#post-11226430Works out to 55 lbs and flat rate shipping of 17.90
