C3 Screw Adjustable Rear Toe Control?

Anyone know how the Guldstrand screw adjustable pivot bolt for the trailing arm pivot works?

I have a set around here somewhere I never used...basically a bushing with an internal thread gets welded into each side of the frame then the adjuster screws into the bushing. loosen one side, tighten the other side changes the toe...I`ll post a pic if I can locate them.