Yes this does help - and thank you to everyone for the info you've provided.
8 major manufacturing changes - it ain't never simple, is it?
I did a search over at the Cummins/Onan etc site & found a couple of places nearby to check with: One is a diesel shop in the same industrial park as my workplace & the other is a truck repair shop one of my friends from the parachute club works at. Small world!
Armed with the part#, serial # and application (mobile welder) hopefully they will be able to come up with something!