Stumped on source of ringing noise!

[Metacom]

A ringing noise is coming from what sounds like the transmission bell housing to bottom of oil pan area.

Past weekend, a slight rod knock was discovered while trying to find this ringing noise, so the rod bearings and main bearings were replaced. After seeing some wear on the rear main bearing we figured that was the source of the ringing.

So the Z sits for 2 days and I drive her around all day today and sure enough the ringing comes back, exactly as before. The noise does not change clutch in or out, it seems to become slightly higher pitched with engine speed. Audible in idle or gear.

We've had the transmission off about 4 times now trying to find what it could be and we're all drawing blanks.

Any wild ideas!?

[t.mcginley.jr]

My only guesses are loose bolts/hardware that will "ring" because of vibration from the engine. I know there's something loose around my shifter/trim area because when I hit the gas it rattles and makes a ringing noise. Could also be something rubbing from vibration like the exhaust or heat shields?

[Metacom]

This definitely sounds more like two parts in constant contact, which is why the rotating/spinning assembly of the clutch/flywheel area is the main suspect...since all new rod bearings were put in.