When building a z80 shim, choose a set of header pins for the legs you are plugging into the Z80 socet on the computer's motherboard that are thin (do not use the the standard type) otherwise the Z80 socket will be damaged. Solder them in first, because the Z80 socket you solder to the shim probably won't let you get access to the pin header once fitted.
On the shim's bus connector footprint, pin 1 is labelled "A11" and is a square pad (all the others are round). Use an unboxed 40 way right angled pin header for this, as shown in the photos on this page, or you may find space is too tight inside the computer, and check the orientation of the header and cable is correct before soldering the header in.
=== uIDE-16 fix for 8-bit mode ===