I've sent some pics to Paolo of my setup, which is a work in progress as I'm building a drawer/water tank system at the same time as permanently installing the 2nd batt, which up to now has been floating around in a marine box behind the cargo barrier. I'm gonna post these up on a different thread as I've done it a bit differently to previous examples seen.

To add to this thread though, planning the battery cable run from the front to the rear I found a large rubber grommet behind the rear left wheel, looks to be in the perfect place to run cable through and into the cargo area. So I'll be running the positive and negative cable along the top of chassis rails, protected with tubing and in through there. Lot easier than trying to run two 4 gauge cables through the trim