[EricH]

There is an alternative to the IFI gearbox. It happens to be the direct design ancestor of the AndyMark Toughbox, which is COTS. I believe they use similar gearing. So, you get an unmodified AM Toughbox from your shop, or get one from AM (send it to a local team, if you get their permission), and use that. It should work about the same as the IFI gearbox. It may even be a little lighter.