Well, I think I've successfully replace all the seals in the lower unit of my 25 johnson. I also replace the impeller while I was at it. There were a few tense moments when the gear shift didn't work right due to some unknown shifting that appartently took place upon removal of the unit and especially when the linkage bolt stripped out the linkage clamp, but I finally figured out the shift pattern and was able to find a screw with a beveled end and wider thread pattern that tightend into the clamp just fine.
I ran the motor in a barrel of water, then checked the oil from the lower unit drain and it was clear, so hopefully everything is ready to go. Not too bad a job, but wouldn't want to do it again anytime soon. Hope to try it out in the lake on monday.