Tom,
You mentioned about the bolts holding on the lower unit. I need to remind you that those bolts also hold the gearcase against the lower unit. So if you remove the lower unit it is possible that the gearcase might seperate from the upper portion and leak a bunch of grease out. It won’t hurt anything if that happens other than make a mess. What I do is cut 2 pieces of 1/2 pipe, slip them over the studs after removal and then use 2 washers and the nuts that came off the studs to hold things together.
George