Replacement parts like cam,crank,block,head and such can be difficult to find or even unavailable for many older engines. Even when available,market price of any 2 can run the bill up. My neighbor had a MF diesel taking up space in his barn for 5 years while he searched for a rebuildable crank. Un rebuildable and not worth rebuilding are often used interchangeably. I wish you all the success but before uncorking it,at least ask around locally so see if it might be wiser investing in a ready to work tractor rather than gamble on a pig in the poke. If parts are readily available and reasonably priced,it could be a fun project and learning experience,,,,if you can afford to lose the investment and buy something else in the event of failure. Who knows,someone might loan you all the once in a lifetime used instruments and tools but it's better knowing before you need them. There might be a silver lining in the school of hard knocks but few intentionally choose having a second go at it. I bought a vintage bike that hadn't been started in 20 years for $2k knowing parts are almost non existent but could get $1k as salvage and $1k lose wouldn't causes me a problem. Dropped it at a shop,spent $800 and sold it for $16k. Luck? No,calculated risk. The bike had set on display at a sports bar for 20 years and when placed closed,bidders there to buy restaurant equipment didn't give me much competition. Had it been a bike auction I would have dropped out long before savvy buyers even slowed down. Point being a novice never walks away with a lights out bargain at tractor auctions. Them old boys can walk around once and know as much as the last owner,possibly more.