Ok, after speaking with someone quite knowledgable, I learned that I would need to do something more in depth than I originally thought. I have a hardware hack working for one 7 segment display but I need to do 4, so I am back to the software side. Here is what I need to do:
Flex -> SerialProxy -> Arduino -> SoftwareSerial -> MAX7219 -> 4 x 7 Segment Displays
So my question is, does anyone have a setup similiar or any code that can help out? Am I missing something or am I doing something wrong?