Simple question, two of the plugs are for the injectors and they replace the two that are on the injectors now and the other two get plugged into the harness that you unplugged from the injector. Male into female pf course . It isn't important which two get plugged into which two on an 03.
Connect the ground wire and you're all set .
Glider got everything pluged in and put back together fire it up everything checked out ok went for a ride everything went great.Thanks for all your help SE103