I have not done this yet, just gathering sources.

Resources

Disassembly video, demonstrating how to remove the Blackberry keyboard: BlackBerry Classic Teardown | Disassembling Parts - YouTube

PiBerry construction guide, indicating nothing special is needed for the keyboard to work: PiBerry 7.5+ Guide – Carbon Computers

Link to buy the PCB: PiBerry 10.0 - Portable Pi Zero 2W from Carbon Computers on Tindie