- iFixit iOpener Set
- T4 Screwdriver
- T3 Screwdriver
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After about 60~90 seconds, use Opening Picks (or a slot screwdriver that's thin enough to fit) to pry open the back cover from upper right corner

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Remove the screws (T4) that keeping the black plate attached to the frame and remove the black plate
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Disconnect all 3 connectors from the logic board and take out the logic board from the Keyboard frame

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Remove the power switch from upper left corner (T3)
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Carefully remove the sticker(?) from the connector and disconnect Touch ID sensor from the connector

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Unscrew the mounting screws around the Touch ID sensor (T3), and remove the Touch ID sensor
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Carefully remove the flex cable used to connect Touch ID sensor
Now you have all the parts to put together a standalone Touch ID device for your Apple silicon Mac.
After connecting the Lightning connector and Touch ID sensor back to the logic board, you can pair the Touch ID sensor with your Mac under System Preferences.
If the pairing step doesn't appear when you go to Touch ID settings -> add a new fingerprint, make sure the Touch ID sensor is correctly connected and try power cycle the Touch ID device.










I have the materials but haven't yet started to tear the keyboard apart. However I will note that the bluetooth "window" (The plastic strip in the metal at the thickest edge of the keyboard) is at the opposite end from the touchID. I would presume that the bluetooth antenna is located there. So either there is a separate antenna (connected by the wide ribbon cable?) or it built into the board at the corner that just barely overlaps that window.
Edit to add: In the photos at the top of this page, you can see a little silver metal bit on the upper-right corner of the tenkeyless board. That is almost certainly the bluetooth antenna. Make sure it isn't damaged on yours.
I also suspect that the metal keyboard case itself and the plastic window aperture are tuned to work with the bluetooth antenna signal, and I would not be surprised if range was shorter when the board is in a different enclosure.
The little round shiny thing on the traces from the built-in antenna is a micro-coaxial connector that could probably be used to connect an external bluetooth antenna.