Boat is a 1986 and has the original "concealed" sidemount control arm. You know - the kind which is just the throttle/shift arm ... the choke and key switch is on the dash. It's a little weather-beaten and I have access to a brand new unit for a good price. How hard would it be to replace this ? I havent looked to closely yet .... but it seems the unit would be hard to get at .... mounted behind the fiberglass liner. Anyone ? Thanks.