That is correct, and I would urge anyone adding another battery to use a
similarly large ground lead for it. Even if you use a small wire/relay
to connect it for charging purposes it is wise to use a regular battery
ground clamp with large wire as sold at any FLAPS for $5 and bolt it to
the chassis. If someone used a small ground wire and then later tried to
jump start the main battery from it, a fire could result. The way this
could happen is if a good connection was made with the red jumper cable
clamps but a poor one at either end of the black jumper cable, all of
the starting current would pass through the battery ground wire and a
small wire one could melt or flame.

Mark

TJ Hannink wrote:

>In the stock dual battery setup found in '85-'87
>non-GL Campers, the auxiliary battery uses the
>identical grounding method as the starting battery,
>using the same battery ground cable assembly.
>
>Here is an old photo:
><http://home.earthlink.net/~tjhannink/photos/Under_Drivers_Seat.jpg>
>
>I have since added a yellow top Optima and a relay
>that uses the on/off signal wire from my headend unit
>to control power to the rest of my A/V components.
>
><http://home.earthlink.net/~tjhannink/AV_System_Diagram_and_Product_Specs.htm>
>
>Thanks,
>
>
>
>