Quote Originally Posted by Elox
Just looking at your proto design, could the back from a Calumet 4x5 (CC-400?) be modified to fit? I don't know if the round rail they use is close to the size you are using. [...]
Thanks for the suggestions. My error, I think, is from my crummy drawings. The rear can be any good existing 4x5 back I can weld or machine to the design. I have your good suggestion in the GOOD IDEA box. Again, many thanks for looking and helping out.

Best,
JJ