What I'm looking at doing is dropping in a very small metal battery box next to the frame rail on the passenger side floor.. with a Zeus fastened cover.. my lithium battery is only about the size of a quart of oil. technically the battery would not be in the passenger compartment.. but it would be accessed through the passenger compartment
I measured last night and it appears I have room in the area outside the frame below the floor between the firewall and orig t-bar crossmember...based on what I have READ, if I were you I'd save yourself ANY potential grief and TRY to mount it there. My floor over there is non-factory 'tin'...essentially tube chassis from firewall back.
