I think they look way cooler with the windshield! Change it to an IO no way! No IO was ever that cool looking LOL, keep it as a pump boat. Hell if you want to change it just go all out and hang a big old 2 Smoke on the back. May run a "lil" faster but will sound like crap doing it! My buddy Chris has one that is almost done being rebuilt. Think it ran about 55 with a stock 454, stock E-pump, A impeller, place diverter and a cam. You can find him over on performanceboats.com he goes by 69sleekcraft give him a shout!