You layout a PCB or breadboard for the Sparkfun flavor (GND, CTS, VCC, TXD, RXD, DTR), but when you begin troubleshooting all you can find is ... following 1×10 header pinout, where the original ...

For example, consider the following 1×10 header pinout, where the original 8-pins are expanded to 10 to allow for power: This is an extreme example, and can obviously be shrunk depending on how ...