I've read that with the Leonardo, it's supposed to be easier to interface with things through the hardware UART through pins 1 and 2.
It's even easier if you use pins 0 and 1.
However, I'm finding it difficult to understand how to tweak the example from sparkfun to work with the Leonardo.
Change Serial to Serial1 if using the hardware serial port or change the SoftwareSerial instance to Serial1.
Also, if it wouldn't be too much trouble, I'd like to understand why things must be wired a certain way.
To ensure that they work. Seems kind of obvious, no?