The wiring is part of the mirror frame. The wiring in the frame is different between the auto-dim ones and the normal ones because

a) The connector on the mirror glass is different
b) more wires go back to the DCM

So, if you have the correct frames it all just plugs in. If you do not have the correct frames you will need to replace them or 'combine' them by stripping some mirrors with the correct wiring (which is a pain to do)

Richard