Originally Posted by angrymelon

Although it sounds like you've already found a solution for yourself, I figured I'd mention other possible options. I'm using the 4000mah Maxamp pack they list for the DF03 chassis. It fits, but it doesn't fit in the "This was designed specifically for this chassis" kind of way. You can get it into the car and close the battery door without modifying anything. Don't get me wrong, it's by no means even remotely close to perfect but it does work.

-melon