To answer "where to begin", that's a good question. We would be able to answer that question if we know the overall condition of the truck and the goal of the truck, I.E. driver, hot rod, refurbish, restoration level. The first order is to take overall stock of the condition and completeness of the truck. If we had some good pics of the truck inside and out and engine bay.we could advise.
Is necessary to get it moving around the area to work on it? or do you just want to see if it starts?
WARNING:
After sitting 47 years, your restart is way out of the ordinary and will take many special precautions before turning that motor with a starter. Have you determined that the motor will turn over by hand and not frozen? Do this in neutral with spark plugs removed. What else do you see that is missing? If you have very limited experience, it is especially important to move carefully with advice from members here. Very nice you have received a "family truck", should be fun.
If you need electrical help/wiring help, give us a good look at the alternator and any numbers on it. Be advised that you can start the truck WITHOUT wiring the alternator and black box, just to see it start. It has nothing to do with the ignition system. We can give you instruction for starting.
Please answer Tim's question about 6V or 12V.
