Behind the PASS seat By PAX(people at werks)
I just had to play with the words.
Since I am running a GM A/C Unit there is just enough room under the 'raised rear deck to set an OPTIMA battery, tight but does fit. I ran the Ground to the body right at the battery location, and the positive lead (welding cable)was run down the center of the A/C consul and exits through a 5/8" hole with rubber Grommet in line and elevation with the Starter. Then I soldered a copper terminal to it and bolted it to the solenoid. Works well till you have to charge it with a battery charger, to jump it off with cables I just land it on the starter post and ground it off to what ever is closest. I would not run a wet (acid) battery due to the fumes it can put off, plus acid spills would not be fun no matter what it gets on.
As for metal support brackets, tire hold down, rear shield, ect. I have several almost complete sets,including jacks, the only thing missing is the J-bolt and wing nut. I have made the J-bolt from all-thread in the past (or I can make you an almost copy of one too) and purchased a wing nut for it in the past. Complete units are available and a pattern for the plywood deck with cut out and mount points can all be provided. Just send me a request via PM or email: rodney(at)opelwrx.com