I'm honestly not sure either, and this is unsolicited advice, but new units aren't terribly expensive. If you're going to go through the trouble to do the job, why not put a freshie in? I thought it was somewhat complicated, and was planning to have a shop do it when I bought a unit for my 87'. I asked frscke if he likes the Eaton units he put it, but I don't think he saw my message. I'm assuming they're working great, spinning both tires, and haven't blown up.