DB9 Wiring help

Hi Fellow Simmers

I am from United Kingdom and have been interested in flight simming for some years, i now have caught the home build bug and have started a Cessna 172 skyhawk pannel, at the moment i am half way through building my first guage its a "Servo Turn Coordinator" with the help of mikes flight deck book, i have made the PCB and finished the electronics but i need help with the wiring of the DB9 plug at the moment i have (+12V pin 2 - main earth on pin 5 loped back to pin 3 for LEDs - +5V pin 4 for LEDs ) i have the two input wires for the servos but not sure what pins these connect to on DB9 plug, 1 - 6 - 7 - 8 - 9 any advise greatfully received.