The rear axle seals are leaking on my GR2100. It already had the Kubota transmission "upgrade" years ago when they had a recall. My question is about what parts to order. I see a transmission kit that includes the housing. Is this the same as the upgrade? If yes, then I already have the "new" housing. Can I just order the seals? Can the seals be changed by removing the wheel hubs or does the transmission need to be split?