Don’t forget the original 6 volt system is positive ground. Keep the 6 V starter - 12 V will spin it and makes starting easier. I saw a kit online to convert the 6 V generator to 12 V.
There are folks using Jeep Cherokee master cylinders.
This conversion would best be done while the front end sheet metal is off.
You can wire it for 6 V (wire gauges) those wires can handle 12 V. If you wire it with 12 V wires, they will be too small for 6 V.
I put a Petronix ignition in my truck to eliminate points. I had no trouble finding brass freeze plugs (Dorman), but the big PITA is replacing the water distribution tube behind water pump.
You need to measure the head length, because there are 23” and 25” varieties.
A couple of other good sources of parts is Vintage Power Wagons and Dodge Central of Michigan.
