Hi wardh, if your only going to be powering some power sockets in the rear then all you will need is the SC40-LR Plug-&-Play kit as this has the controller and cable to be able to connect from the cranking battery to the Auxiliary battery.
You may need to fit a 30 amp circuit breaker on the cable going to the rear cargo area if it hasn’t already go one in place and the only other thing you need is the battery.
There is no need for a battery tray and the kit has the Land Rover battery bracket supplied.
If you have an Anderson plug at the back of the your D3 then you will need the SC80-LR Plug-&-Play kit so you can charge two Auxiliary batteries at the same time.
Cheers, drivesafe.

