If fitting a dimmer switch it does'nt matter which way round the wires are connected, with the power to the lights OFF, fit one in the terminal marked Com and the other in the terminal marked L1. Even with a normal rocker switch it does'nt matter as the whole switch can be turned upside down, if need be, and screwed back to the back box. Zinggys advice about rubber gloves and working live should be ignored. Bet he's got spiky hair as well.
good luck
baz
baz
November 2007