I started on a wooden tool tray but gave up when I found that my four-leaf springs had dropped the body to the point that the space available wasn't much better than the MMC one. Indeed, there were signs of the diff casing meeting the underside of the original. Sulk, sulk
John makes a good point. The space is behind and to the sides of the diff. I have a good 3" of internal depth on my wooden concoction and the ply is only 12mm thick over the diff. Just ask if you need any dimensions and I can measure it and make a little sketch.
