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As far as "no bump steer", I have news. The original system has very little bump steer. There's no reason to swap out your stock suspension to get rid of bump steer that isn't there. If you had a mustang, different story.
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I have a Longacre Bump Steer Gauge used by race teams. It measures to the 0.000" !
My car measured with very little bumpsteer. With all stock geometry.
Almost no car will have 0.000" bumpsteer. There will almost always be some small amount that may be insignificant, but still zero.
Just changing your caster setting will change you bumpsteer. So no system out of the box can guarantee ZERO bumpsteer or the same 100% bumpsteer amount for every car. But it can be an insignificant amount that is optimum bumpsteer or near optimum. With the right equipment you can often times reduce it even further.