The install was in 2012 and possibly they're not making them anymore,  I may still have their email address - I'll check.  I used an ARB diff locker compressor to supply air and the included ARB diff locker wiring loom to switch the CDL - here's a few pics .....
Attachment 120867Attachment 120869
The left rocker switch is the air compressor the centre rocker switch is an isolator to prevent accidental activation of the CDL and right rocker switch is the CDL on/off, there is a vid I'll link to at the next opportunity ...