Cool, thanks Mark. I'll have to fab one up. I was thinking of making it from Trex or something similar. I did end up figuring out why it wouldn't start and also why I was nuking the wiring. The 230 cca battery was good but buzzed the solenoid. I ended up with a Deka 350 cca that also buzzed the solenoid. I then found that Jacobsen energizes the field winding by pulling in the regulator coil with the switched side of the starter solenoid. if the field doesn't get energized the generator won't start the engine and the solenoid will buzz. Vice versus, when I was tinkering with the regulator I tripped the field winding with the engine off and it tried to start the tractor and nuked the field coil wire.
I'm trying to wrap my head around a way I can use a diode to keep the field winging voltage from trying to start the tractor when the regulator messes up. I could wire the start coil pull into the low amp side and then use a diode for the charging side. I need to sketch it out and see which way the current flows in start and charge. Still haven't found a decent wiring diagram (might have to draw one).
Also in other news, my buddy who owns a bunch of these is off work with a busted hoof so it'll be a while before I get the manuals to scan.