[Kahuna]

I have a '76, 20' Seafari with the I/O. It is actually getting repowered as we speak (i need to post something ob the Main forum about that, but that is another story) so i am going to be in the same position you are in, looking for a prop, as the old 4cyl that is comming out was pretty tired and the lower unit gear will be different. i looked at putting that V-6 in mine, but the problem i saw was the motor was only "3 cylinders long and 2 cylinders wide" if you know what I mean vice the 4cy which is 4 x 1. I did manage to find one with the V-6 in it, and it sure looked to sit stern heavy. I agree, that chain was probably a perfect counter balance. I also agree, that i would love to have the extra power beyond the 135 that the 4cyl offers, and i did look into the bracket and outboard route. One of Strick's buddies on the sight here really set up a '75 I/O seafari with a bracket, and looks and seems to perform great. The thing i keep going back to is that it is only a 20' boat. i opted for the perplan reserve bouyancy vice the extra speed. After runnning it a few times, that chain may end up back where it came from. Best of luck.