My AC seemed to be blowing weak and one day, no air would blow out the vents.

I looked under the hood and looked at the vacuum module on the driver's side by the firewall (has 4 ports - manifold, AC, BB (brake booster) and SC - what the hell does SC stand for?) and the AC vacuum line was broken. Check here first if you experience this. I made the mistake of taking the center console apart and looking at the back of the AC unit first because this is my first Mustang. At least I know how to take this apart now. It could use some tightening up to reduce rattle.