Frame rails only

[CG]

On long bed trucks 2 wheel and 4 wheel are the frame rails the same? Not talking about any of the cross members, just the rails. And tossing in 3/4 tons, are they also the same but heavier gauge? Or does the gauge get heavier with the one tons?

As far as burbs and panels go isn't there some sort of kick up (or down?) that makes those rails different from the trucks? Or maybe its just the cross member in the rear?

Basically I have several extra sets of whole frames now (nothing for sale or cutting up) in all of the configurations Ive mentioned. Trucks 2X and 4X, half and 3/4 and the same with burb/panels.