I stopped at a local shop that specializes in solar/batteries, and stumbled across a welding cable that is super flexible.  4gauge wire bends super easy!  It's almost like an extension cord, but 4 gauge wire, pretty darn impressive.  I wish I would have stumbled on this long time ago.  Wrestling even with 8 gauge wire can be problematic, let alone heavier gauge wire. This welding cable is 100% copper and stranded, so it's no problem to use with batteries.  4 gauge locally sold for about $2.10 a foot, and I'm sure it would be cheaper in the states. The 6 gauge was $1.40. Again, great stuff.  Highly recommended!

Troy