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Seals for driveshaft: Lowerpump seal 493-5112, Driveshaft seal 508-3186, upper driveshaft bearing 493-3105. Lower pump seal is sealed to the impeller housing & aluminum housing. I had my housing machined down enough to install two driveshaft seals, one up & other down.
Remove the aluminum pipe for the shift shaft & replace the O-ring sealing the shift shaft. Check the aluminum housing for cover threads to be pulled out causing three leaks from high threads. I have never broke a shift shaft. Never force it, The motor must be running to shift the transmission. Be careful not to leave the shift slider open, it will migrate oil behind the piston & lock up shift assembly.