I purchased a $20 soldering iron kit from ebay. It came with a case, stand, wire strippers, and a bunch of other accessories, it did the job for this small bit of soldering, but I would recommend spending more on a decent iron if you intend on building more projects like this, or have more buttons to connect than I did. I soldiered some jumper sockets onto the Teensy board and used some Alligator-clip jumper pins to test out each button functioned correctly. You could just solder wires directly onto the Teensy board, but using jumpers was easier to prototype.
You will need to install the Teensy drivers and the Arduino IDE from here. Once you have your Teensy board plugged into USB, set it to be detected as a Joystick/Keyboard and it should be detected by Windows when you plug it in. Initially, the amber light on it should be lit up or flashing. Open the ‘blink test’ sketch and edit this script to increase the flashing rate, you can find the tutorial on how to do this on the PJRC site, it will give you an idea of how easy it is to update the sketch on the board. You just need to set the Teensy board to be used a Joystick, and you can download the sketch I used here, it is based off an example file, with the Hat switch test commented out.
I used a bread board to make testing the buttons and potentiometers nice and easy. Most of the buttons are quite easy to connect as they have only 2 terminals, the Start Engine button was a bit more challenging as it has a LED back light to connect up, and the large yellow ‘Eject’ button has the ability to be set either on when pressed, or on when not pressed.
To house everything I used a Jiffy box from Jaycar, these are cheap, come in a range of sizes and are made of ABS plastic so are quite durable. I went with the biggest size (197 x 113 x 63mm) as I need a bit of depth for the Eject button, I wouldn’t recommend making it’s much smaller though, as once you connect up everything with wires it can get a bit cramped for space. Another alternative is to build a wooden box, I’ve seen some people build nice looking ones with laser cut wood, or repurpose an existing container. I did think about using an old ammunition box but thought it might be had to access the revised side to wire it all
up.