Hello, I have a 1997 Seaswirl 2600 Striper with the Volvo penta 5.7 tbi engine with the sx outdrive. I would like to get a duoprop on it, I hear they drive better and get better fuel economy. I don't have the gear ratio info or model #. My boat is in San Quintin Baja Mexico. Would anybody know the cost, where can I find a used one, would it actually be worth the trouble and expense...etc... Any help will be appreciated.