2 6V battery mod

Looking into first major mod for The DeLaPODza and am going to do the 6V series line up. I did a search and didnt find anything specific to a write up on this mod and will start this thread off by asking for tips or tricks on doing this with a TT, I am motorhead and have worked with electrcals on cars but I hear the TT are a lil different, so any help is appreciated. I will go shopping around the island later this week and am sure I will be limited on the make of battery I will be able to get.

Iv got a Napa, Carquest, and Walmart. Im not positive on any other places that carry batteries on my island. And im thinking of building my own battery box to have them locked up.

From what I've read extensively on this topic, Trojan T-105 batteries seem to be the gold-standard for 6v batteries. They aren't the cheapest out there, but with proper maintenance (water levels checked at least once a year and topped off with distilled water; ALWAYS left on a 3 stage computer controlled charger when not being used) they can last 10 years or more.