As far as I am aware, there are no problems with the wiring diagram (2166) as far as the actual wiring is concerned. There is, however, a diagram in circulation that shows incorrect internal wiring within the alternator - there shouldn't be an outer connection between the alternator coils at 5 o'clock - but this doesn't affect the rest of the wiring.
The finger from terminal 9 should contact the upper ring on the switch rotor (the DC circuit). When new, the switch was housed in a rubber sleeve - if a tight fit can't be made in the nacelle, a couple of keep plates may be needed (on terminal 9 and the stud opposite) - in which case, the plate on terminal 9 will need to be insulated so that it can't earth out to the nacelle. The whole switch is in the live side of the circuit and does not need, or have any connection to earth.
Hope this helps,
Regards,
Eddie.