Farmall 140 12 Volt Wiring Diagram

Hi everyone. Just purchased a 1940 Farmall A tractor. The wires had been removed. It has the push-pull ignition switch and was converted to a 12-volt system. I am in desperate need for a wiring diagram. The ones I have found on internet have not shown a clear picture of the wiring diagram. Any help would be greatly appreciated.. I looked in my Farmall 140 Part Catalog and there is a change at s/n 26801 to a 12 volt system but still retains a generator. There is no mention in the part catalog of an alternator and the 12 volt light switch is numbered as 376851R91. The diagram also is still showing the voltage regulator being used since it hasn't been revised to an.

The "1 wire" Delco 10 SI needs more rpm to excite than a "3 wire" unit, But many do not realize that a small amp output "1 wire" unit self excites at much less rpm than the big units. In my experience, a 37 amp "1 wire" Delco will excite at 1/2 the rpm of a big 61 or 72 amp "1 wire " alternator.. Does anyone have a good wiring diagram for the 140. Currently restoring my grandfathers. Serial number 44503 JKK. It is a 12v tractor with key switch and push button starter. All the diagrams I have found just have just ignition switch or are for tractors with positive ground. Also looking any.