Mike,
Thanks for those drawings, much appreciated.
On the subject of catwalks, there was a post on the HMVF forum a while ago identifying that the catwalk rails taken off a Bedford MWC were 15 inches apart. When you look at the attached photo (based on a 2 gallon can being about 9-3/4" wide), 15 inches seems a bit wide.
I would say 11 inches maximum?
Owen.