Fitting a Dimmer switch

[ChrisRance6]

I want to fit a one gang 2 way brass dimmer switch replacing an existing normall flick switch.
On my new dimmer switch i wish to fit I have a Wavey Line, l1, L2 And earth.
coming out of the wall I have live neutral and earth, I realise i have to connect the earth to the brass dimmer.
Where do the existing red and black wires go?

Is it red to L1 black to wavey line?

 

[jj4091]

either way will work, but have you got enough depth in the backbox?

 

[ChrisRance6]

Yes i have
red to L1 Black to wavey line and earth to earth?
thanks very much

 

[securespark]

The cpc should be connected to both the box & the switch plate.