the main difference in the solenoids is the housing seal/washer....The nitrous uses a nylon washer, where the fuel uses a rubber washer. Rubber will freeze/ crack as nitrous is very cold. You will have to take apart the solenoid, change the fuel piston(small cylinder with what looks like a pencil eraser on the end)with the nitrous piston, and change the o-ring/washer gasket with a nylon one from a nitrous solenoid. Hopefully I didn't confuse the hell out of you.
