On nano avoid A6, A7 as they don't have digital capability. And D13 due to arduino on board led Other boards pin support may vary. Matrix wiring is intended for momentary switches, you cant use toggle ...

The button states could easily be read by using an Arduino’s analog input. A Pro Mini model was chosen for its small size as it could be housed in the radio compartment of the dash.

Arduino pins, and almost everything else at a standard hobbyist scale, are 0.1" pin spacing - so I just soldered the sense wires to some 0.1" headers I have laying around.

Read before Only arduino pro micro have Gamepad native support, if you want to get it recognized as a controller within the game, make sure to use arduino pro micro. Otherwise only SimHub will see ...