Generally speaking, you do not want bearings or bushings to be substantially on threads. The more load, the more it's not good practice. We go through great lengths, by using AN bolts, to keep everything on the shank, including mounting tabs/brackets and then use spacers/washers then nuts.
Doug, Like almost everything to do with suspensions, there is no one magic minimum bump-steer number. Less is always better. Yes, the ideal is zero but that MIGHT (not likely) be obtainable through a very short part of the range of travel. Anyone that hasn't looked at a bump-steer curve should do so to better understand what's going on.
Furthermore, a number is somewhat meaningless unless the method of measurement is defined. Ideally the steering angle introduced by suspension travel should be kept to a minimum. The condition and compliance of the suspension system can affect the accuracy of the measurements and whether or not the driver can sense some bump-steer. Excessive B-S will be felt.
By nature suspension systems are dynamic and things can change quite a bit through the range of travel. To make things more complicated, what the driver senses can be influenced by many things.
The spring/shock system has nothing to do with suspension geometry other than limiting the travel in both bump and droop. Once you start modifying a suspension system you really need to check everything for max performance. Changing ride height and the wheel/tire package can effectively changes where in the travel range the suspension is operating which will change alignment (as BOSS said) and preferred settings. The good news is that minor changes may not be that significant for a street car with street rubber. An alignment will be necessary, as BOSS said.
The car was designed around a static ride height and specific tire diameters. If you significantly deviate from that thing can change including optimal wheel alignment specs.
Donny, In your case having a popular wheel/tire package is a good start. Next determine the static ride height. As a broad rule of thumb don't go lower than what keeps the effective lower front A-arm parallel to the ground. Important: meaning imaginary line from about mid-point between inner mount to center of the ball joint. If the inner A-arm mounting points are higher than the center of the ball joint, that can be acceptable. If they are lower, then you can have excessive camber gain through upward suspension travel which is generally not good for street cars. Then you have to make some decisions. How low can you live with. How stiff (higher spring rates) a suspension do you want to live with. Is the car for show or go. Aesthetics are important to many people. I think we all like low but banging on the road gets old very quick. Shocks/springs and bump-steer adjustment come next. Enjoy the learning experience.