We have obtained a rear hybrid diff from a 2014 Mitsubishi Outlander, and it fits into the front subframe. A lot of work will still be involved to install it but we think it will be minimal cutting and welding to the original subframe.
When you're battery dependent, you want to keep all consumption to a minimum.
For the classic mini, lights are the biggest drain. Can you increase your eco-credentials with a kit of LED bulbs, headlights and flasher unit? We are thinking of finding appropriate suppliers and putting this kit together. Even an interior bulb set could be an option in one package.
Working from the scanned images of the classic mini A series gearbox, this has now continued with the mock up of the motor sat on top of it.
Garry continues to work on this, refining all the time.