Probably meant a 230/250 engine from 1974. If that or the 4.3 v6, or any small block with a 700R4 automatic/with overdrive. It will all bolt into an 1984 C-10 frame, it came that way from the factory.
I picked up a late 1990's NV3500 5 speed for it....still hoping the 4.3 will be a good choice...trying to figure out a set of hanging pedals for it now...was trying to do a hodge podge from something newer .....thinking an aftermarket might be a better set up in the long run...trying to save money on these truck builds will bite in the butt every time...
Thanks for all the insight....you guys are awesome...
MikeC