I finally got all of this together. To recap:
460 engine, 360 flywheel and clutch, cast iron bell housing. Now here is the weird part. When I tried to bolt up the four speed transmission the input shaft sleeve bottomed out on the clutch hub. I went to the salvage yard and found a '74 two wheel drive and bought the transmission for a spare because the truck wasn't going to be there much longer. on a lark, I took the sleeve off of that transmission and it was .125" shorter than mine. I swapped those out and everything bolts up fine.