[oldman3]

Brought this pic back, as you can see I also used 1"X2" by 1/8" wall rectangular tubing along the back (two rows). You can do this however you want to get this attached to the cab braces. What I did was weld small angles on the braces level from one side to the other. Cut my rectangular tubing a little long and clamped in place. I then took 2-1/4" I.D. exhaust tubing bends (I think they were 45 degree) (or bend to match curve of cab), sliced it in several places on one end, moved the slices around to overlap the rectangular tubing and the other end butted to the 2"X2" tub (may have to shorten the 1"X2" tube to get this to fit. Once everything is fitting good, tack it in place At this point you should have both sides tied together. Now go back and start welding everything in solid (this also includes the 3" plate at bottom of door opening). Move around a lot to keep from pulling anything out of shape. I then added the angle pieces for additional support. Little overkill on my part, but I didn't want it to move. Now we have both cab rear door openings tied to the rear of the cab, nice and solid.