Have a driveshaft question

Don't know if this is the right area for a driveshaft question or not, and I did a search and did come up with an answer. The truck I picked up was without engine/trans, and I believe I found the front section of the driveshaft in the bed. A guy I work with has a rear section.

My question is, If I were to use the 350/700R4 combo from my 1/2 ton parts suburban, could I use the front section of the driveshaft from the suburban with a rear section for a 1 ton truck? Would the length be correct? What about the splines were the 2 sections come together, are they different for a 1/2 ton shaft and a 1 ton shaft?

Thanks for any help you guys can give me.

i know on mine i had 2 1 tons. a 75 std cab and a 85 crew cab and the shafts diameter was diff and the splines on the carrier bearing were also diff. now old gm auto trans are usually the same spline