So after lots of testing....well a bit anyway...we needed to build a new chassis, if only because we'd drilled so many holes in the old one!
First make the battery holder which is also part of the suspension. Here it is.
Well that's spectacular isn't it. It's very basic, is made from a piece of acrylic tube, one end has a fixed plastic plug with a battery contact permanently attached and the other has a plastic spring holding the other contact in, which is held in place with a screw. The tube itself forms the central pivot of the suspension.
The two halves of the chassis were updated to accommodate the positioning of the camera as well as the main controller and attachment processors.