it does read the gears, easiest way is plug in those japanese overide boxes, http://store.shopping.yahoo.co.jp/kong/y0000002983.html, about $130 if you have contact in japan. You are unlucky you dont have one fitted already from japan, have you checked behind your screen ? Otherwise you could spend hours trying to work out the wiring, as from memory probably around 40 wires into the xanavi unit. Think Andy does a solution for the M35's, not sure if this would be the same in the C34s.