Yes, you should not use 4 poly bushings in the rear, especially with a panhard.
Same thing with the GW lowers and a panhard. All these pieces will induce bind (when combined together). You can get snap-oversteer which is when you reach the limit of the suspension, then suddenly it binds, and the car reacts (negatively) to it.
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Darius Rudis
Roadracer: Home built t-arm/panhard suspension powered by an S-trimmed motor :-)
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