Yes, manual hubs and manual shift transfer case is the most reliable.
Here are the years and models:
http://www.therangerstation.com/tech_library/TransferCases.shtml
They are of course hard to find.
There is a unit called the Shiftster($60), it is installed in place of the electric motor so you can shift transfer case manually.
http://www.theshiftster.com/
Draw back is that you have to get under the vehicle to shift it.
If you are a 4-wheeler it isn't a big issue since you have to get out to lock the hubs anyway, when starting the off road journey.
But if you need to shift in and out of 4WD because of weather or temporary road conditions then it can be a wet and dirty business getting under the truck, lol.
The true benefit is that at least you know you will have 4WD when you need it, no more back of the mind wondering if electric system will work when you need it