I recently rebuilt the rear end and changed the cover with the one from american Muscle.com GMS 8.8 Rear End Differential Cover (79-10) at AmericanMuscle.com - Free Shipping! and I wasn't sure about how much oil it needed. So far its up to 5 quarts and its still not coming out of the fill hole which I thought it should have done by now. I thought stock it recommended 2.8 but I'm not sure if this is good or normal, I don't know if something's messed up or I just need to add more oil still. Anyone have any experience with these covers or the Ford racing one? Any suggestions?