Some slop here is needed, as you'll weld the pinion to the crown gear if it's too tight. If it isn't whining loudly, it's probably ok.
You have slop all the way from the pinion shaft to the rear wheels and it adds up.
pinion shaft play, output shaft play, multi-piece ds play, rear gear play, axle play. tolerance stacking varies this quite a lot car to car.
Try driving a little differently, you can work around this. A few more revs before shifting and a touch of gas just as you engage the gear loads the drivetrain and prevents a lot of this. This is SOP for most MT RWD cars, historically.
2014 Premium GT, SGM, Brembo, Auto, Tech, Comfort, etc. GT500s, Steeda UCA, VMP auto N/A tune. 100 shot nitrous on BBR tune. Best e/t 11.38 at 120.85
2012 Premium GT, Candy Red, Brembo package, 3.73, MT82, Comfort, Tech, et al. Procal tune, Roush UCA, UMI poly LCA, GT500s, Steeda red bracket, Hoosier 28x10x16 bias drags. Best e/t 11.91 at 115.23 RIP