Given the relatively short wheelbase and narrow track width of this car, a tiny bit off, like under a degree,isn't going to be a big deal on the road.
Obviously if you can get the car totally square, that's ideal but, remember this car has huge soft rubber bushings with lots of deflection stock and the car manages allright with that so don't fret too much.
Thrust angle is the angle in which the front and rear axles deliver their force to the road.
As I said, I wouldn't put adjustable lowers on a road car. Pinion angle is the best thing to be concentrating on getting right on rear setup and that's best done with an adjustable upper. Adjusting pinion angle with the lowers changes the wheelbase and centering of the axle in the wheelwell, which brings other problems on.
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