Simple answer is the 230 family engines use the same bellhousing and flywheel items as the small block V8 Chevy including any trans that fits the V8. 235 parts don't fit on the back of the 230.
A complete open shaft driveline will be the easiest and best way to use a 230 in the 51 you have. You also lose around 125 - 150 lbs with that swap. Almost like a few more free horsepower.
