SPC lower control arms are not ST legal last I checked, they use a spherical bearing on the inboard side instead of elastomer.
https://www.spcalignment.com/product/67660
"Get the ultimate in performance and handling with this stamped arm featuring our new xAxis Sealed Joint which performs like a pillow joint but lasts like an OE joint."
Cheap and easy (should be <$300) is the whiteline version that puts a polyurethane bushing in that spot. Although I've had issues with it slipping (pretty much entirely due to street driving) - haven't roughed them up yet in an attempt to get better bite, but that's all I can think of to fix them without spending $$$.
https://whitelineperformance.com/us/...-kta216a.html?
Seems like swapping the upper control arm is the latest hotness, but at >$600 I'm not excited about it, at least you can shed some weight and stiffen up those bushings in the process.