KFChickenShim | allow SDVX 4 cabinets to easily upgrade

Here are the instructions for setting up the board for use. I will not cover PCB assembly, all of the components are pretty self-explanatory in terms of placement on the board (they all have exactly one spot).
The first thing you'll want to do is remove the original BemaniPC from the cabinet. You'll need to disconnect every cable and remove the PC entirely, as the KFCA board is inside the PC case. In the below image, the board in the red rectangle is the one we're after. Once the PC is removed from the cabinet, you'll need to remove the KFCA board from inside the PC case, which means you'll need to unscrew the case of the BemaniPC so you can get inside it. NOTE: If your cab is a gen 1 cabinet, your PC may look different from mine, but the process should be similar in terms of removing the IO. Once the top is removed, you should see the exposed motherboard of the original PC. You'll more or less want to unplug all cables from the motherboard, to make it easy to remove since the KFCA sits underneath the motherboard. In the picture below, the connector in the red rectangle is the serial coming from the KFCA, and will be plugged into the KFChickenShim board.
Copy the libacio.dll file from your SDVX 4 installation and paste it into your SDVX 5 installation, renaming it to libacio32.dll.
Copy kfchicken32.dll and kfchicken32.exe into your SDVX 5 installation. The KFChicken release thread says you can use the 64-bit version and the SDVX 5 DLLs but this doesn't work correctly as of this writing, so use the SDVX 4 modules and 32-bit KFChicken.
Setup your kfchicken.json file as below, making sure to change the com field to the appropriate COM port to match whatever serial port the KFCA is hooked up to (can be found using Windows Device Manager, under Ports (COM and LPT)), and also the right settings to match your SpiceAPI port and password in gamestart.bat (covered next). NOTE: The default kfchicken.json file has the baudrate field set to 57600. I personally experienced unplayable knobs/analog inputs until I changed this value to 115200 instead.
Modify your gamestart.bat file to start KFChicken before starting Spice, and also to make Spice expose its API. Change the port and password to whatever you'd like, but make sure the kfchicken.json file has the same settings.
If all went well, you should finally be good to go, and SDVX 5 will be running using the old IO board!