It's a TKO so there are no converter bolts. Dumb question, but is it typical for the same issue to happen with the pressure plate and/or flywheel bolts? I'd have to drop the trans to retighten all of these obviously which is a pain to do in the driveway.
The noise started on its own. I have done lots of things to the car, but the only engine related things have been timing and carb tuning, and an intake swap so I'm not sure I caused the noise. Anything is possible though, I do have a tendency to fix one thing and mess up another.
The engine is the original 350 with a PPR stroker kit, KRE heads, I think the compression is around 10-10.5:1. I'm going out there again to try to get a video of the noise.