1989 2.3 mustang help find a short maybe. My mistake.

[4cylredfox89]

I plugged this EGR vacuum solenoid connector in backwards while replacing, then got codes 31, 83,84 then 31. I replaced the solenoid then it disappeared with 83 84, then 11. Next day code 83,84 then 31 c..

Someone said I could have a short and now I'm stuck on how to find it, went on YouTube only to find myself not wanting to screw this car up anymore that it is.