My son and I just completed BBORR, we had an absolute blast!
About halfway on the second leg the car started shaking pretty badly, it lost power and gave several messages on the DIC. Mostly to do with the differential. He throttled back, downshifted and increased the throttle and the car recovered.........mostly. He drove it in, at speed, and we finished without dropping below minimum speed. Good job.
The passenger rear sway bar bracket failed. It appears to be a stress crack, part is shiny and part is rusty. The other side is cracked more than halfway through.
Supposition from here on:
The bushings are a little thick and the bracket was under quite a bit of stress. The washer/spacer idea is spot on. I suspect that the brackets broke on the end that was tightened second because that end would be out of position and "pulled" tight.
Fortunately there was no angst and I called BMR and got new brackets/bushings headed this way.
A thread on the "washer" mod
https://www.camaro6.com/forums/showthread.php?t=617405