I've got a '73 25' Luhrs with a junk 318 in it. I would really like to put a 5.9 cummins in it. I know them pretty well and feel that it would be much more reliable. I've found most of the parts I need to install one. I don't know what the 318 weighs, but the cummins is just under 1100 lbs. How much of an issue is that? Also, what are my options for a prop? I can't go much bigger where it is before its too close to the hull. Can I move it back any or will it cavitate? This is my first inboard. Thanks, Mike