Re: 165hp to v8
Welcome to iboats.
You'll need a complete motor including exhaust manifolds, Y-pipe for the exhaust, and a way to mount it on the sides. Your inline has a front motor mount. That will be of no use on a V-anything. Not all boats made for inlines have the structure to support a V. I can't answer about the bell housing, but that would be the least of your worries at this point. If it's a GM V-8, there might be a chance. If it's anything else, no chance.