Recently acquired 48 8N looked like it was going to be OK. It hadn't run in 5 years but after adding ATF to the cylinders and doing some rewiring it fired right up. Everything looked good with 40# oil pressure. After running it a while it started to smoke on acceleration. Son-in-law found the problem, when he pulled #4 cylinder plug wire it stopped smoking so we know where the problem is. My question, is it possible to just pull one piston and do what needs to be done, maybe rings, maybe more. I am a parts replacer not a mechanic so would probably have to hire this done if it is even possible. The other option is to use it for a donor tractor.