promacjoe2:
I don't recall you saying which Arduino you are using. If you're Arduino has a USB connector on it, why don't you use it. They make a USB panel mount connector for this type application. No way you can get it confused. And you don't have to keep up with a special cable to use it.
Its a home brew atmega1284p based system. There is no usb port. I use an external ftdi usb ro serial board to program it