Does anybody know...?

According to my Reference guide 93 5.0 Drivetrains are as follows

5spd manual Standard2.73 Optional 3.08
4spd auto Standard2.73 Optional 3.27

I assume by 93 all Mustangs had 8.8

The tag on the rear (assuming it is still there) will give better/more reliable info though.

Good Luck with the gears.
 
I think that's the entire rear end that he's looking at.

You can just replace the ring gears alone. All you need are 3.73's for an 8.8 rear. Spline counts don't matter. SHould be about $120-190 for a set of Ford gears