Where's this noise coming from?

Sounds like the torque converter bolts hitting the transmission inspection plate. My slant did that after hitting a rock and bent the cover. I know it would theoretically do that when not moving, but no noise idling in N, but made noise under load. Maybe the crank shifts axially slightly. My 82 Aries made a similar noise, but it was a torque converter bolt unscrewing and hitting the block. Same deal w/ more noise under load.