Buick/Olds: Buick 87 Engine Knocking, rod bearing, metal flakes

Question
Engine started knocking on business trip and I had to drive it home 500 miles haven't driven since. Changed the oil just before trip. How would  I fix it.  I have already put a new transmission, starter, spark plugs, cables,  she was running great and now this.  Any help would be greatly appreciated.

Answer
What sort of knock is it? Is in on top, or underneath?
Check your oil, by rubbing some off the dipstick between your fingers, you are looking for metal flakes in the oil.
It sounds at this point, like you could have a problem with a piston, or a rod bearing. It is remotely possible that it is a pushrod ( in the valve train)
I'll stand by for your update.