Well Volks,
As I am moving my way around the 87 syncro GL to Westy conversion, I have come to the front seat swivels and 2nd battery area of the conversion.
I have decided I am going to install the swivel under the drivers side as well even though most of you tell me you never turn the drivers seat or set up the front table much. 
I figure I need to "have it" so I can also "not use it". (grin)

I have come up with a way to bolt the swivels in place so I can still pull the whole thing off and not have it welded in the way, which brings me to my topic.

I am installing a nice 1000 watt inverter I picked up at Costco awhile back for $69 It looks like it will fit nicely under the drivers seat and I can make some large wire connections to the 2nd battery. 
These inverters seem to really want good heavy connections to the battery to produce decent amounts of AC current. 

My main question is if you were wiring up the 2nd battery from scratch how would you wire it in? I do like the simple relay design VW has it seems to work well and do the job, no?

I also would like to use a smaller battery than stock size, and here's my main question, are there any really good small deep cycle batteries that will fit into the compartment?

I have seen some nice ones at West Marine for sailboats etc that look good but good grief a hundred bucks?

I have heard there is a BMW battery that fits into the compartment and is smaller. 

I have found a fellow here in Sausalito (Arc Battery) who provides a deep cycle battery that is the exact size of the vanagon battery. Its darn heavy though.

What guage wire is used to connect the two batteries together?

Doug