What do I do to use the ARDUINO MICRO PRO / ARDUINO LEONARDO rather then the LEOBODNAR BU0836A

I am building the Mod 3 737 throttle. It is costly and also mailing is difficult to get the Leobodnar to the US. According to Karl's instructions I would need 2 of the Arduino Micro Pro or the Leonardo but doesn't the Leobodnar have a sketch in it? And how do I use two of them?

Just near clearification as I can get the Micro Pro or Leonardo very quickly and just a few dollars rather than around $50 US including shipping for the Leobodnar. I know in the YouTube video he mentions using the cheaper one but no additional information.

Thanks, Jay Beckham