I realize that this is not in my leauge, or vintage of truck but, I have always wondered what does the accuating, is it vaccum? solinoid, What makes the shift in the transfere case to the lower gear.
I done mine by interupting the vaccum line on the front axle. Could a switch be in stalled to intrupt the solinoid, but still get the lower gear?
The concept that was/ being discussed was how the old new proccess [GM 73 and later yrs etc] full time 4 wheel drive was by changed. Remove the spider gears and put in a couple others. Get away from the front axle turning. and then add Hubs. A bit of work.
Marv.