This is the Case for the Pico Calc Mod to use a Raspberry Pi Zero 2 WH.

If you like my design maybe consider: 
https://buymeacoffee.com/ironatmmi

Software

Thanks wasdwasd0105 for the Software implementation in Bulleyes:

https://github.com/wasdwasd0105/picocalc-pi-zero-2

Trixie implementation:

https://github.com/ironat/picocalc_trixie

Videos:

https://youtu.be/wgE0R1M0_ZE

https://youtu.be/cJGrIinqjVM

https://youtu.be/A5BDa9PmUcA

Materials:

All links are amazon affiliate links:

USB-A: 

Euro: 

https://amzn.to/4n3RMVt 

US: 

https://amzn.to/47Suyxb 

USB Adapter for Pi Zero:

EURO: 

https://amzn.to/4n0IGJ4

US: 

https://amzn.to/46esi1W 

Header:

(EU) https://amzn.to/47EIOcV (Pack of 10)

(US) https://amzn.to/4gyLYBu (Pack of 15)

Forum Topic: 

https://forum.clockworkpi.com/t/raspberry-pi-zero-2-on-picocalc

PCBWay Project:

https://www.pcbway.com/project/shareproject/Picocalc_Zero_Mod_for_Raspberry_Pi_Zero_2W_1c0c1a06.html

Gerber Files:

My Github page for the Gerber File: https://github.com/ironat/ZeroCalcGerber

How to connect PI with Adapter Board