The tricky part will be locating where to put the holes in the bottom of the cab AND the sides of the frame.
I have a '49 cab on a '47 (or '48) frame. Since the '49 cab came with the later ('49-'55) rear mounts, it was easy enough to figure out where the holes in the frame belong. I attached the mounts to the bottom of the cab, placed 3/4" board between the mount support plate and the frame, let the mounts hang down and pushed them against the side of the frame and marked the frame through the holes in the mount.
