I've never done it, but I believe you just have to rewire the throttle and elevator pots, and move the centering and ratchet mechanism to the proper sides. The Futabas I've worked with seem to be symmetric (and I'm sure Hitec is as well), so swapping the centering and ratchet mechansim should be fairly easily. If the entire gimbal assembly is easily removed as a whole, you could just swap those and the rewire the aileron and rudder pots so they are on the proper sides.