48bomber, I viewed your pics with interest. I am working on '48 B12 for a friend. Nothing heavy yet, mainly fuel delivery-rust in tank, and small wiring issues. Although I have not finished examining the entire machine, it looks very original and sound. It looks very much like yours and at first glance they could be mistaken for one another. I have no experience with BIG BOMBERS but am learning through this forum. I do have some info on Chrysler flatheads from old MOTORS manual and 1945 US Army manual on the 236.6. This motor says T120 IND and might be 251.
Thanks for the input to this forum. BIGDAVE