Get it, once it's gone, it's gone. Flywheel ring gear is cheap. $82.00 through Case/IH, aftermarket one slightly less. Other than removing the engine, they are easy to replace if you have an acetylene torch. Remove flywheel, heat ring gear, and light taps with a hammer, it drops right off. Lay the new one on the flywheel, heat it up, and tap it on, boom, you're done.
I have a 656 Farmall row crop that is my "big" tractor. I onlyuse it for making hay, to run the MoCo, and round baler. LOVE that tractor..!!