First thing to determine is how far into it will you have to go. That is, check for rot in floor (spongy?), transom and stringers (test drill looking for soft wood and/or wet??) around the engine bay. If you have done that and found rot, you need to be prepared to go really deep into replacing possibly the floor, stringers, and/or transom throughout the boat... If you pull the engine then its a good idea to pull the outdrive and see how the transom, mounting bolts and mounting holes look. I am new to do this myself but well into full resto on my boat.