mdogg, I'm putting a 37 cab on a 40 chassis. I set the cab on the frame and mocked up the radiator support just to see. The front two cab mounts line up perfectly, the back two mounting holes are off by approx. 1 1/2". No problem, just drill four new holes. Apparantly the 37-38 cab is a little shorter, but it fits fine from the firewall forward including the rad. support. Iwould think the 41-46 frame would be the same. Jeff
