Update: I got the bell housing off, I was thrown off by the old school hinge pins but they came out easily. I'm going to replace the greaseable gimble bearing with a sealed unit. I have a bellows kit with new hoses and clamps. I have a couple of questions.
1. The bellows kit and shift cable is from SEI, is the quality on these parts decent or should I go OEM? I would like to not have to do this job again for a couple years.
Don't know about SEI quality--I'd assume on par with decent aftermarket (sierra) but not quite OEM. My last sierra kit is 5 years old and looks perfect. I've also seen differences in shift cable quality. In general I think the ones with the plastic coated core wire are pretty good. I'd stay away from bare metal. I also haven't had a problem with sierra pumps. I'm replacing them before they have a chance to go bad anyway.
2. Is there anything else I should consider doing while I'm here? This is my first time doing a repair like this, lots of experience with cars but I don't want to miss anything.
Upper shift shaft seal on the bell housing. Although that's easy to access with the drive off, so could hold off on that if you wanted.
3. I'm going to replace the water pump, also from SEI. I see that the general consensus is to do it with the drive off. I was hoping to do this with it mounted because I don't have a drive stand. How much trouble will I run into if I do it this way?
No way I'd do it with the drive on. Doesn't take much extra time, and IMO it's just way easier to get it right. I've never used a drive stand.
That transom hose on the other hand. Get OEM. It's a bear to replace that, and the OEM hose is molded better/fits easier.
I also wouldn't bother with the trim senders. Not sure on the MC-1, but on the A1G1 they're a PITA and relatively worthless anyway. The gen 2's are easier.