What he said^
But two things that stand out to me when reading this... A/C removal turns me off. Second, was the car painted the original factory color, or a different factory blue than it came as? If different, although it looks great, can hurt the value to someone looking for a nice stock one.
It’s very subjective, but I would say if your car runs and drives nicely, and is rust free, you would be looking at $8-10k here in IA where clean ones are scarce.
Lastly, there were many more than 4 years of fox body Mustangs made.