Factory leisure battery wiring help

[Phil_G]

Bondage and buggery going on there…( no sorry, I see it’s a foot )

The green guy isnt smiling....

 

[Epic-Rob]

OK so i am just fitting a couple of Aux batteries (one under each seat) with a DC-Dc charger and small inverter.
but i am getting conflicting info on where is the best place to put the main earth to, i was told by my solar installer to run it to negative on starter battery but that involves a lot of fu%j ing aroung getting it under mat ant trough into engine bay, other info talks about electrical noise and to somewhere like engine block or to factory earth points.....
on my last van i earthed it to the seat base bolt which seemed to work ok but it may have been totally wrong.

am taking +feed from the VW installed Aux feed under seat.

 

[rod_vw]

Any -ve connection can be made to one of the factory provided chassis ground studs of which there is one under each front seat plus others around the vehicle. There are files on this forum showing where these are.