What is wrong if your 1991 Escort GT is pouring transmission fluid out somewhere between the automatic transmission and the motor?

Its your transmition line, and you should take it to a shop that specializes in Transmitions or else you are going to be ripped off. Parts are $20-$40, and labor should only run you 1.5 hours. Good luck. Could also be the Main seal! If so, sell, sell, sell!

although selling would depend on your honesty, if someone asks "is there anything wrong with it..."

if its pouring out, dont drive it, until its repaired. then get it repaired, because it may not be worth selling as a car that doesnt go.