if the car hits the tires rear hard you may want to try the upper hole. many people have different ways of adjusting the bars but from the words of cal trac him self first try a nickel gap again if you hit the tires real hard. if you not having any luck try just touching the bar to the spring. then if all else fails 1/4-1/2 turn preload the springs with the bar. put the shocks in the middle and start there with your shock adjustment. ive been playin with these for years and for my application about 6-7 clicks workes best for the shocks and i run 1/4 turn preload on the lower bar position. its alot of messin around hope this helps. the holes for the front mount will change your instant center and lift point from the suspention. make sure you are or somone that weighs the same as you sits in the driver seat when adjusting the bars other wise the car will leave sidways