What's going on? Noise?
Fixing the rear is a relatively straightforward job, as long as the person doing takes a little time with setup. 8.8s get more finicky the bigger the ratio gets.
You can double check by jacking the car up, marking the DS with a grease pencil or similar and turning the wheel or shaft. Then you have the exact amount of rotation of the wheel for the rotation of the shaft. I use a particular axle stud for counting. Instant ratio check and physical confirmation, no calculation.
2014 Premium GT, SGM, Brembo, Auto, Tech, Comfort, etc. GT500s, Steeda UCA, VMP auto tune, 100 shot on BBR tune, best et: 11.38 at 120.85
2012 GT, Candy Red, Brembo, 3.73, Tech, Comfort, etc. Procal tune, Roush upper, UMI LCAs, Steeda red bracket, GT500s, 28X10X16 Hoosier slicks, best et: 11.91 at 115.23 RIP