Another vehicle to consider could possibly be an '89 to '98.5 Dodge with a Cummins and standard transmission. Early automatics had no electronics as well. No electronics for the engine to run except the starter and grid heater, and thats not necessary except in very cold weather, and even you can live without it. I'm no Dodge fan, I just like the Cummins, and they happen to come in a Dodge.
Upside to the Dodges: More power than a CUCV, better highway speed, slightly better fuel mileage (I've seen as high as 25mpg with my '96, 30mpg with my Durango with swapped in 4bt)
Downside: Not needed to run the truck, but there are other electrical systems that can be damaged, leaving you without a working speedometer and other things. Also more complex to work on and maintain, since they are "modern" vehicles.
Just throwing out other options. The CUCVs are great for simplicity though, and also very cheap parts replacement (except for the 24v part).
Jim