Well if this is going to become a track only car (more or less) the only problem i see has already been mentioned..

if you think about your car like a sea-saw/teater-toder(what ever you call those things) your takeing away front wheel weight which you want for FWD and putting it behind the rear wheels which is essentialy your pivot point so in a small way it would help to remove more weight from the front. then theres the ADDED weight of the extra wiring, and the ballast weight if you add that. your trying to get the lightest car possible to get better times if this is a track car.

well thats my $.02

I can see the point that you made Pete. I know that you want at least SOME weight over the front wheels for traction in straight-line races. And you are right again about adding the extra weight from the new cables.

The more I think about it, the only way relocating the battery to the trunk would be beneficial would be for auto-x or SCCA-type events. And who the hell runs Bonnevilles in those :?:

I retract my previous statement. For now I will keep the battery where it is. My custom-built battery cables aren't holding up as good as I would have liked, so I am going to redesign those, maybe lead-reinforce the cable-to-terminal points.