> Note on use: I am looking at adding a 30+ amp amplifier for a new stereo
> that will likely drain the auxiliary battery and I concerned that when the
> aux battery is charging, while driving, it will draw too high of an
> amperage across the existing wiring to the starter battery.

I cannibalized a jumper cable and ran one long strand from the alternator to the main battery.
That is a 4 gauge wire, very heavy.
I ran another length of that from the Surepower 1315 battery separator that sits in the main battery
box, out and down the vent hole, under/across the van outside then up into the aux. battery area
by drilling a hole and grommeting and sealing that hole. So, I have larger capacity/capability for
charging than the OE wiring. 

The long length from alt. to main battery, is run outside, under the van along the coolant lines,
supported by zip ties. I got that idea from another lister (Mark Drillock) whom was having Vitrifrigo
energy maintenance and aux battery recharge issues while out on an extended trip. This seemed
to fix (as far as I know) that problem, so I adopted it.

I also have portable/moveable solar charging and except for a Vitrifrigo current sensing problem,
the system otherwise is working real well. The panel is an 80 watt.

I have overkill on the UB12220 batteries, 4 in the aux box, 4 under the kitchen sink cabinet....
176 AH. That set up provides plenty of power for my uses, which are the fridge, interior lighting,
which is mostly LED, and music from the radio. I plugged #3 fuse lower slot directly into the aux
battery bank to run the entire dash.

bob