Yes my boat was a I/O, I removed the motor added a 25 gal gas tank to go with my two 20 gal Saddle bag tanks giving me 65 gal of gas.
I also have a 25 gal made by me live well that I keep under the motor cover till I need it.
The cover also makes a great bait table and you can even sit on it to jig!
I take a lot of people fishing, and my boat is kind of a group project and boat.
I took a survey, and all but me wanted to keep the cover after the conversion, so the I's have it!
I found 2 sites that sell extension kits, But they are not cheap, around $500
http://www.baymfg.com/index.asp
http://www.marineparts.com/partspage...ories/acc8.htm