I am finally to the "Dry mount it and let it rust" part of this. I did purchase a donor unit - I noted that a couple of days ago. The donor is a 1989 - I misread the date code. The treat was getting the junk genny extracted from the good engine. There is no doubt as to the disposition of the old rotor. I cut the windings off with a hacksaw, punched the wire pack out of the winding frame, tore the winding frame off the center shaft 6 plates at a time after I 'loosened things up' with a sawzall, then took the center shaft off with a torch and hammer. I have amassed quite a pile of crap. The good news is that the new genny mounts right up to the engine.
I may dry fit the original field winding unit and head over the new rotor just to see if it all aligns. If it does, I may even give it a test run. If the problem was my in my rotor, I'll have a repaired Ag Tronic.
QUESTION: The old Aggie used a pair of windings for the AC output. The PowerMate uses a single winding. They both have a center tap. If the original center section (windings) and the head end of the generator physically fit together, is there anything about the new rotor that might mess things up? I sure don't want to break it or overheat anything. My choice is to sell either a newer PowerMate or an old classic Ag Tronic.
Now let's hope that the new generator head does work. It was running a heavy load when the connecting rod in the engine blew. It should be fine. So I'm told.