You are on the right track going with the southfork. They build the best factory tunnel on the market. If you can get away with it do not use a jack plate. Tunnels run the best with the lower unit close to the tunnel. If you do have to run a jack plate to get the motor height correct stay with a 4" setback. For a prop I would go with a powertech sw3. It is made for tunnels,has the gumbo cup already casted into the prop. They make it in a 4 blade too but in my experience they are too heavy and loose holeshot.
http://www.ptprop.com/index.php?page...mart&Itemid=46