Fitted this over the last few days.
I’m happy with it.
Somehow with the Puma Defender I just can’t see enough behind me for parking – must be some kind of optical illusion as it’s exactly the same dimensions as the 300Tdi and I had no problems there 🙂
Anyway, fairly straightforward to fit –
The ‘Garmin BC™ 30 Wireless Backup Camera’ is powered by the reversing light.
For the Head unit (Garmin Navigation GPS) I dropped the cable behind the dash.
The original connector plug converts from 12V to 5V so I’m using a 12V cigarette lighter socket with a flylead hooked up to a fuse tap.
Not a bad setup and works really well – unit switches between GPS and camera as soon as you stick it into reverse.
Reverse… 
SatNav 
Camera