I suspect removing the backup battery for a day would accomplish it. It might also remove everything from FLASH forcing a complete reinstall.
I’ve never felt like wandering down that path, but reloading the current firmware then restoring everything except the system and globals from a full backup from that firmware would help. Exporting the All-layouts file prior too for later reimporting should result in the system being current, all layouts, presets and cabs in place, and the global settings back to the defaults.
