Industrial slant six?

The only differences your likely to find would be the Balancer, and possibly the carburetor. The timing tab and mark may be in a different location. I don't know about the distributor.

The parts off of your car engine will bolt up. Some of the accessory mount points may need to be drilled/tapped, but that you'd have to verify.

The engines are the same castings. If you have an automatic tranny, make sure the crank pocket is the same size. That's year specific, not a difference between the industrial and automotive engines. 67 and earlier have the small crank pocket, 68 and later have large. To use an early transmission on a late model engine install a bushing.

Get the identification stamped on the tractor block and tell us what it says. (Passenger right side on the deck surface the head bolts to near plug #1 in most cases.)

CJ