Okay, here is how it's done:
install all your suspension parts but do not install the bump steer kit. Set the camber, caster and toe to where you want it. (This is a whole other subject)
Drive the car around and let the suspension settle. Springs and shocks and bushings all need to settle in. Also, only tighten up control arm bolts when the car is at ride height, NOT with the suspension hanging. This keeps from preloading the suspension with twisted bushings that may later settle and possibly tear down the road. If they are spherical bearing ends it doesn't matter, but rubber or poly bushings should always be done this way.
Once the car is all settled in, carefully measure the ride height.
On a coil over car (a real coil over car-not a strut car with a coil over a strut) you measure from shock eye to shock eye. Since a strut car doesn't have this you will have to pick a place to measure from PERFECTLY, no close enough or guesses are acceptable here or anywhere in the process. Do it right or don't do it at all.
Strut cars suck *** so this is going to be way harder than it needs to be.
Here I am about 500 years ago setting the bump steer on a coil over car with the coil over removed. Notice the dial indicator and the level on the lower control arm.
Also notice how much room there is to work.
Same car after painting and several track records (for reference)
Okay now you have a precise measurement for your ride height ( you may have to go from the exact center of the spindle nut to the fender well and mark it for accuracy because you will be refferring to this measurement later)
Jack up the car, ideally on 4 jack stands with the car perfectly level.
Take off the front wheels and remove the front springs.
Yes you have to do it this way.
Put the strut back together and use a jack to raise the lower control arm back up to where your measurement said "This is ride height".
Center the rack, not the wheel-the rack. Adjust from this point always.
Carefully measure the length of the stock tie rod from center to center. On a stock rack you may have to mark a spot on the tie rod with a tie wrap or something and measure out to the center off the ball.
Everything pivots from here so this is what matters.
**This part is optional, but will save you tons of time in the long run.
Cut apart one stock outer tie rod end housing with an abrasive wheel. Don't wreck the stud or ball, this is the part that you want.
Put the newly freed tie rod shank and ball back into the steering arm and seat it with the nut. VERY CAREFULLY measure from the bottom of the steering arm to the center of the ball. Mark this down, it matters.
Now take that measurement and stack the exact amount of spacers on the bump kit so that center of the ball of the spherical rod end to the bottom of the steering arm is exactly the same as the stock ball/shank. This will get you very close to stock and save a ton of time-but feel free to do it the hard way if you want and skip this step, but you'll thank me later if you do it. Otherwise, just throw any amount of shims on there and guess. You'll see why this is important later....but hey, whatever.
Install the bump steer kit with that precise shim stack and at the same length as the stock tie rod. Adjust the length so it is the same as the stock setup. Your front wheel's should point perfectly straight ahead.
Lock the steering column so the wheel can't move. Make sure its straight ahead when you are done.
Now install the bump gauge. Set it up so that you can check the bump steer for at least 2" of bump and 1" of rebound. This is how we do oval track cars. These big heavy street cars on a road race track may need more travel but this is the method you need to follow. Twice the bump and half the rebound.
Now that you have the gauge set up and everything is set at ride height, mark where the indicator touches the aluminum plate with a sharpie.
THIS IS YOUR BASELINE!
(carb/brake cleaner or lacquer thinner or acetone removes sharpie like magic-have some on hand)
Now use a scale or ruler to accurately mark bump and rebound travel on the plate in 1/2" increments. You are creating a map here. This map is everything.
Zero the gauge.
Slowly jack the suspension up to the 1/2" bump mark. Read the gauge and mark it down. Go another half inch and mark it down and so-forth for 2 inches.
Go back to ride height and zero the gauge. Now go down and do the same marking it on your paper.
You are making a map.
You will see something like 0, +120 +250, + 375, +675 toe change or whatever.
You are mapping the toe change curve
Use + for toe out and - for toe in. Your numbers will be different, but you get the idea...*****s moving either in or out and you need to know which way, how much, and where its doing it.
Add or remove shims to change this curve. Check it again from 0 to 2" bump. Mark it down and compare to the last settings.
Notice the difference. Is it better or worse? You are trying to hit zero. You may not get there but you want to be as close as possible.
(Its easier if you only do bump first and then dial the rebound settings after the bump is perfect)
Repeat this process over and over and over until you have as close to zero as possible. Any bump steer left in the suspension should be in the + direction...never in-always out. Zero toe change on road race/autocross cars is optimum.
Now do the rebound and see what happens. Adjust as necessary.
By now you have a nice map of various toe changes and should have a real grasp of how a tiny adjustment can make a huge difference in toe change.
Repeat on the other side.
When done, Set the total toe in on the car on an alignment rack or with a trammel bar if you have one.
Here is something that most guys don't realize:
When you change the caster (not camber) it will raise and lower the steering arm slightly and your bump will be off so you'll need to check it again.
It's best to set the camber/caster/toe before this process and reset the toe when finished.
Let me know how this goes for you.