Hydra-Matic
What are your questions (or, what are you stuck on)?
If you have a 1954 GMC short-bed Hydra-Matic drive train (in the "donor" truck), it is a fully enclosed drive shaft. Is this correct?
I do not know about a GMC 1/2 ton long-bed, but if it is the same drive-train as used in a 1954 GMC 3/4 ton, it has an open drive shaft. Is this correct?