Sorry I don't know what it looks like but I have a suggestion to your problem.

Many cos. sell a small solar panel for charging small batteries. Since the current flow is low you might be able to find one you could prop up in the front window (car facing south) and it would act like a trickle charger.

Here's one source I've dealt with. You have to be a little bit of an experimenter with these things but some are plug-and-play. And at least you'd have the protection of your LoJack when you are away.

http://store.sundancesolar.com/trchforcatrr.html

Good luck.