Revised the battery tie-down. This version is pretty close to the same weight as stock, if not lighter. Materials needed to make one like it are around $10.
http://stores.ebay.com/8020incgaragesale
I am using the equivalent of the 2020 metric T-slot profile, and you can get an 18" long piece for less than $5 off ebay. Just add the appropriate size button head cap screws and you've got all you need. Use a chop saw (or even a hacksaw - just make sure your cuts are square) to cut the pieces to size (one 8.5 inches, one 3, and one 1), and tap the ends of the two short support pieces to match the cap screws. Mark your locations and drill four holes in the long section: two for the J-hooks, and two access holes to tighten the button head cap screws.
I've got the J-hooks on the wrong ends in the picture, but you get the idea. I'm probably going to plasti-dip this thing, but haven't bothered yet.
EDIT: Did a half-assed Plastidip job on the tiedown. Looks ok for what it is, and the dip provides insulation as well as even better grip on the battery.