Thank you. I just did as you suggested.
I am wondering why the GT500 cover will come with another vent?
You plug the vent on the cover and continue using the Stock vent on the axle tube.
2014 Mustang V6 3.7L 6-spd manual, with MGW shifter, Airaid CAI, BBK shorty headers, Corsa Sport axle back, strut tower brace, JLT oil separator, GT500 differential cover, BG Synchro Shift II gear oil, Redline differential oil.