Update:
Got a Gilmer belt drive water pump kit for a small block chevy off of ebay.
Had a tapered puck made from S7 steel to fit on the crank and bolt up one of the pulleys. I'm going to run a jackshaft to the engine, then run the clutch off of the jackshaft to the wheel so the front to back on the chain can be easily aligned, since the engine crank sticks quite a ways out from being in alignment with the rear sprocket.
This vid is of a bracket I am making for the jackshaft, a rough sketch of how it will bolt up to the azusa frame in solidworks:
https://youtu.be/GRTD68_tIog
The engine crank adapter. Basically a puck of steel with a tapered bore and holes to bolt up the sbc water pump pulley