Dave, IMHO you'd be much better off finding a boat
that already has an inboard. The costs of all the parts & pieces; engine, trans, prop shaft, prop shaft strut, prop, thru hull, muffler, engine mounts, shift console & cables, engine panel w/ key and guages would be on the order of $10,000 ++ not counting the engine bed preparation, drilling the hull for a shaft log, mounting the prop strut and getting all that in proper alignment. Just way too much $$ and effort.