Rob - I guess it's a mixed blessing for you, but I'm glad you will keep the boat! You've put a lot of work into restoring Mango Madness.

You should be able to rebuild the engine without any problem. You could even keep the boat in the water, disconnect the shaft coupling and winch the engine out if you wanted. I built an engine stand using 2x3 studs and recommend you get the engine on the stand in the boat immediately after pulling it off the mounts. It's easier to manage that way.

If you have a standard shaft seal, it's easy to keep the water out with the coupling disconnected and shaft slid back. It's also possible with a dripless seal, as I did that when I took the transmission out 3 years back. I just built a strongback and clamped it in place to hold the stainless collar against the carbon seating surface. Good luck!