Welcome to the forum. You've come to the right place for answers and assistance. There are quite few do-it-yourself builders here who have installed all sorts of power plants on bikes. If you're interested in the larger, bulkier engines that will not lend themselves to an in-frame installation you might want to explore the rack mount; Where the engine is located over the rear wheel. Have fun and keep us posted on your build.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"