Military Vehicle Repair: converting m1008 to 12v., amp alternators, stock chevy

Question
how difficult is it to convert a m1008 6.2l diesel to a 12volt  electrical system?  and is it worth my time?

Answer
Hello Steve,
Everything on your 1008 is 12 volt except for the starter, and the relay that operates the starter. There is also possibly a big resistor on the firewall that cuts the 24 volts to 12 for the glow plugs.
Even though there are two alternators, they are identical. Both are 12 volt 100 amp alternators. They are interchangable.
The only difference is, the alternator on the drivers side is grounded to the block, and it charges the front battery.
The alternator on the right side, if you look closely, the ground does not go to the block. The ground is actually connected to the stud on the firewall where 12 volts is tapped from between the batteries.
In other words, it starts between the batteries, and charges the second battery.

I have seven of those trucks at work, and considered converting, till I found all this out.
The most expensive part would be to get a 12 volt starter.
Then connect the batteries in paralell, rather than series, remove the right side alternator and keep for a spare, and remove the resistor from the glowplug circuit by using a jumper from the firewall connector to the relay.
All the lights, guages, fuel shutoff solenoid in the injector pump, etc. are already stock Chevy 12 volt items.
But I stayed 24 volt because I have access to spare parts from a military base.(Legal...I work for a government agency).
Ask me more about them any time. We work the daylights out of them, and I can help you out.
Good luck,
Van