The front end, a-arms, strut spacers, and some of the subframe where all modeled in SolidWorks to check for proper angles, arm lengths and figure out the ball park for correcting the bump steer. When I built a 3" drop down subframe, I had to move the tierod location up roughly an equal amount to minimize the effect. But, the a-arm pivots also got moved in, toward center 3" per side, so I could run longer then stock arms, minimizing suspension angle changes with travel. This helps with ball joint binding. Some how, I got it right and reduced bumpsteer slightly over stock.
I modeled the back suspension too, had to figure out where the top arm, front pivots had to go to get the right axle bite for traction. The other concern was pinion angle changes when going from the stock 5" of travel to the current 9" of travel. It was worth the time spent at the computer, the car, other then trophy truck amounts of body roll, handles great and hooks up in the dirt and on pavement extremely well, it never gets any wheel hop...
-Jon