I don't think the guy is gonna be welding bridges ! Welding On a truck and welding on a bridge are completely different. Having done both, I cant even think of the similarity, except looking at the bead and knowing what to look for. The Dual Shield is worthless on a truck (due to material thickness), but I can see using the 7018.
My advice is keep a notebook, and when you find what works, jot it down, as well as the material and thickness. Then pretty soon you won't need it anymore, and it becomes second nature.
