This stuff is pretty good. I bought a gallon and ended up using all of it. It seemed to cover pretty well but I sprayed 3 coats anyway.
One gallon can was enough for everything on the car I was working on ('61 full size)...frame, inner fenders, core support, under hood, air cleaner, brackets etc. If it's available at the local paint store then I'll probably use it again.
http://melrosecorvette.com/gm-chassis-paint-1050104/