Thanks for the prop info, I will check this out.
Info that I have been told on changing lower unit so far is that the connection between the lower unit and shaft is threaded and red locktite is used as sealant / thread lock. Wire for power head runs from the lower unit all the way to the foot pedal and must be fished through the shaft and cable to foot pedal.
Any info from somebody who has actually done this would be appreciated. Sounds like the tricky part is removal of lower unit from the shaft. If not done correctly, the shaft threads could be ruined and would need to be replaced