Since the battery box was the only area of the new truck that was rusted I set about replacing it . It wasn't exactly straightforward with the DCM battery box. Maybe it was because it was a big truck, but none of the holes lined up great and it interfered with the running board mount, so some modifications had to happen. I also retained the original support which wasn't really rusted bad so it still bolted to the running board bracket and was supported.
While doing that I also upgraded the battery cables, which were way too small (someone had replaced them with just standard 12 volt cables) and since the optima battery was so small I decided to parallel two. Holy cow what a difference in starting. Spins it over much faster and almost instantly starts, even when cold . Before if left any extraneous load on, even a turn signal running I couldn't start the truck. I guess with the small cables the voltage drop was too much. So technically I have 1600 CCA now and 200 minutes of reserve. Hopefully these optima's last a while because they are pricey.