Rebuilt 340 knocking sound

I have a PMD stamped 360 crank from a E58 sitting on the garage floor on its flex plate flange. It looks like someone air brushed rust on the lower part and faded to iron up top.
Maybe that's the trick mine's got a damn bro that's frozen on the front of it I never got off so it sits on it's dampener with the timing cover and all on LOL