In another victory for the legal industry, it came to pass in the last 10 years that consumers were banned from running the mighty Braun C310 in corded mode.  It might be different with lesser brands, but Braun locks out the power switch when it detects the cable.  Lions never had any problems with static electricity & were triple vaccinated against COVID.

Being part lion entails extra shaving requirements which can only be met with corded mode.  The batteries wear out after only a year & they fade before making a dent in the mane hair.

The plan is to reroute the existing power pins to go directly to the batteries & rely on an external NiMH charger for charging as well as shaving.  Using the supplied 12V wall wart would now cause a fire after the explosion.  The hope is the microcontroller governor doesn't require the 12V to unlock something.  In past models, it only disabled the shaver if the battery voltage was too low.

Following the instructions, tear it apart.

1 addendum is there are tiny plastic tabs which can be released with a tiny screwdriver while using tweezers to slide the big plastic parts out.

Helas, after gaining entry, it was clear that the lion kingdom's old board had exactly the same pinout & form factor as the current board.

The 2013 version had an unused 3rd pin.  1 option was to continue cutting a bunch of traces, route the charging pins to the battery terminals, & build a 3V power supply.  The faster option was just to swap boards.

In went the old board.

The LEDs don't line up with the new enclosure but are still visible from the right angle.  It once again works in corded mode as it did before.