Upper A-Arm Washers and Alignment

Maybe some of you have followed some "problems" I have had with alignments. I have a Z51 Magride car.
My "problems" all started when I removed ALL the Upper A-Arms washers.
Yes, GM says to remove only 1 from each bolt, but I removed both.
I did this to be able to get enough camber in to mount wide tires
and not have them rub the tops of the fenders.
This worked.

But I have not been able to get a decent alignment to "stay".
Particularly in the front.
The last few alignments, I have not been able to even get close to
factory specs. Increase camber and screw up caster. And vice-versa.

So I decided to go back to "square one", and go with OEM wheels and narrower tires. This involved putting all the washers back.
But even after this, I still couldn't get back to OEM specs, let alone my more aggressive settings.

So in desperation, we moved some washers around (in the front).
Essentially we removed all the washers from the front of the A-Arm, and put them all in the back. So zero washers for the front part, and 4 washers for the rear part of each A-Arm bolt.
This allowed us to get closer to desired specs, but still not as much as we wanted.

This past weekend (at an autocross), I determined that the right front wheel was about 1 inch further back than the left front. This was rather obvious. What the heck ???????
Maybe the sub-frame has shifted? Or ???
I measured the wheelbase....
left side was about 107, right was about 106. Stock is 106.7.

So yesterday back to the alignment shop.
First, let's put all the washers back the way they should be (2 for each bolt).
Second... set the eccentrics to mid point.
Third, drive the car around a bit to settle things down.
Fourth, re-do the alignment.
Can't get what we want.
Left front 8 caster, -1.1 camber
Right front 6 caster, -1.1 camber.
OK, drive the car for an hour or more all over the place.
Do alignment again.
WOW !!!!!
7.2 caster on both, -2.1 camber on both,
and 106.7 wheelbase on both sides.
And, by the way, the sub-frame can NOT move.... it is "pinned" to the frame.

So... my experience... remove ONE washer, do NOT remove two from all bolts. And keep things equal.

I'm sure glad I got this settled out after all this time.

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Upper A-Arm Washers and Alignment