D-Jack replied:

2nd paragraph should read 'draw power only from the battery under the bonnet'!!!

Member - 120scruiser (NSW) replied:

D Jack
I have been thinking the same thing for the past 3 weeks as I consider which new car I will purchase to upgrade from the Prado. I am thinking of a dual cab hilux with a Metal Form Industries tray.
Derek from Affordable Batteries, a member and advertiser on this site should be able to help you out. Here is his link.
Site Link
Hope this helps
Scott

drivesafe replied:

Hi D-Jack, there’s no problem linking the two batteries together but 6mm ( which is actually 4.5mm2 ) is way to small. If the batteries were side by side 6mm would be fine but even somewhere else in the engine bay and you need at least 8B&S ( 7.9mm2 ) but for a battery located at the back of the vehicle you need 10mm2 minimum or you will get to much of a voltage drop, particularly while the fridge is running.

You will need both positive and negative cables and you need to fit 30 amp circuit breakers at either end of the positive cable.

Cheers

obee replied:

Never earth via the chassis if you can help it. Stray currents equals corrosion. Many electrical faults in old cars used to be caused by earthing lights etc thru chassis. Might be ok using the main beams on a proper chassis but have to make sure the main battey has a good earth straight to same.

My opinion anyway

Owen