That's the weakest spindle out there for an a-body. I wouldn't run them with a /6, I don't care what any aftermarket parts supplier said. I'll see if I can get some pics of the differences in the spindles.
Thanks Jim, I looked for late model spindles in all the yards around here and found nothing, probably taken by all the dirt trackers. Maybe I'll have better luck with 10" drum spindles. Aerospace only lists a kit for the 9" drum, guess I'll call to see if they can do the 10".