My 2 cents:
1) more motor mounts look bad. I would replace. You can do it yourself and save a bunch of $$
2) if possible, remove the coupling off the end of the shaft, remove the cutlass bearing, and then slide shaft out of the boat. It will clear the rudder (barely), and you need to remove the cutlass bearing to get enough play in the shaft. You need a tool (can be home made) to press the cutlass bearing out.
3) If you can't get the coupling off, then you can cut the shaft off, and remove it in pieces and then remove the cutlass bearing (using just a hacksaw blade and chisel).
Assuming the original bronze shaft, inspect for cracks, wear at the stuffing box, and straightness. I think a new shaft will be in order, and with new motor mounts and alignment, will probably smooth things out.
Greg