84 GMC C2500, V12 powered

[cayoterun]

Is it ok for a grown man, (72 yo at that), to cry or do we like new challenges?

The motor picked up a low rpm knock. Below 1,000 rpm, it sounds baad, increase the rpm and it goes away. Finally dropped the pan and one head. No cuttings, or chips of any kind anywhere. Has without a doubt been rebuilt, standard bearings in rods and mains. Pistons .30, and cylinder walls clean, smooth top to bottom. on the ones I've checked. While I have it open, I'll keep going and check all 12 cylinders. If I don't find anything, then will slide the tranny back and recheck the fly-wheels. It's possible I failed to torque all the bolts good, or a used auto flex-plate I used could have had worn bolt holes. I sure want to find the trouble if in the motor, because I don't want to ruin all the hard to find new parts in there.
I was lucky when I mounted the motor. I have room to drop the pan without having to pull motor mounts loose. V-12 tidbit: The pan has 40 5/16 bolts holding it on.

Cayoterun