Car isn't starting with out the other side. Unfortunately for you that other side of that connector you need is in a 94-98 Mustang. You're gonna have to find one at a salvage yard and take it out yourself. Maybe you can find one already removed.
I assume you're also missing the harness inside the passenger fender. That one has the Ignition module and timing spout. It also connects to your missing connector. Also runs to the CCRM module (black box in front of the radiator).
Let me see if I can find pictures.
Go to 8:29 of my video. Do you have this wiring harness for the passenger side fender? Has connections for the A/C, MAF, IAC, CCRM, etc.
View: https://www.youtube.com/watch?v=2FPW6LmAsUc&t=11s