For my Model Ms I've ordered and soldered PCBs from an open source project that are drop in replacements for their controller PCBs and convert them to USB A plu

For my Model Ms I've ordered and soldered PCBs from an open source project that are drop in replacements for their controller PCBs and convert them to USB A plus QMK firmware. (I'm going a bit by memory, as I had to stop the project for a while and still have to switch a couple of them, but can look that for you if you're interested)