UMI’s rear spring spacers may be just  the ticket to achieve that perfect stance or prevent tire rub. UMI’s zinc  coated, laser cut mild steel spacers are available in 1/8” and 3/16” thickness  and can be safely stacked. They provide an easy way to fine tune the rear ride  height of your GM A, G and F-Body. No cutting, welding or drilling required. We  recommend these for fine-tuning only, and maximum adjustment amount is the  responsibility of the installer. Normal installation position is on the upper  perch although lower perches may have adequate height (F-Body lower perch only). 100% manufactured,  tested and raced out of Philipsburg, PA – USA. P/N 0063 is for one 3/16”  spacer.