Rebuilt 340 knocking sound

Hello. My torture continues. Got just about done with my 68 barracuda build. I bought a rebuilt 340 about a year and a half ago on here I primed it. Used high zinc break in oil never revved it up very high. Drove it in total just about 75 or 80 miles. Just drove it to get exhaust done , an alignment, top estimate etc. on the way home from the alignment shop I noticed it started to sound a little different. Also my oil pressure at stop signs was getting way low. When I sped up it would go up a little bit. Once I got home it was starting to sound like a knocking in the lower end. I drained the oil and it had a silver grey look about it , way dirtier then oil that only had 75 miles or so. I put a new filter and 5 qts of new break in oil and it still doesn’t sound good. It has oil pressure when I first start it but as it warms it gets down to almost nothing. I did a compression check on all 8 cylinders and they are all 150 psi or more I’m stumped. Anyway going by a machine shop to see when they can get it in, at least the rotating assembly. I’ll post a couple videos. Tell me what you think

Very generous! :thumbsup:The only better offer the OP will get is a refund from seller.

Bought a year and a half ago, I would never refund a penny.

Who knows what was done in a year and a half. Not saying the OP is lying, just in todays world is anyone telling the truth? Sorry.

I'm betting it hammered out the mains when the oil pickup screen was filled with crud. I've pulled many engines down and most pickup screens are full of crap and coked up oil