Ok, I have done more research on batteries than I ever wanted (
http://www.stealth316.com/2-dynabatt.htm )
I may have found the best solution for me;
A Miata battery!
This one:
http://www.apexbattery.com/miata-bat...batteries.html has close to 500 CCA's, 28 AH, and weighs 25 lbs... (this comares to the Dyna-Batt or Odyssey battery which has only 280cca's...) It should perform as well as a full size battery for my use (no major aftermarket audio or other electronics).
What makes it really better than anything else is it's size! It actually fits in the right rear hatch area with the plastic bin removed and a few inches of trim and insulation trimmmed away... No structural changes, no loss of tool tray or spare tire either!
Also, it is a truly sealed battery that requires no venting...
I will take pictures of the process and the finished product when completed!