Just a comment...which really only matters if you use your truck as transportation...this stuff harbors water and moisture like a demon and if you're in a place where it rains / is very humid most of the year, you might not like the rust bubbling that trapped moisture can encourage. The capillary action from the underside is also pretty bad in my experience. If your truck stays in the garage most of the time, I don't suppose it is any problem. A friend in high school put this stuff on his 51 and also had the dealership undercoat all the fenders after that. It was a wetter than usual summer and by October he had to take all that off, repair the rust and repaint. Every single bolt in the bed had a bull's-eye of rust around it.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end