What is this noise I’m going nuts!!

2007 Silverado 2500

Started making this scraping noise. It increases with rpm. Not the belt, I took that off and it still makes the noise. I thought a bad lifter, but rockers look normal. I hammered on the catalytic converter but didn’t hear anything rattle in there. Sounds more like it’s coming from the flywheel but nothing looks off there either (see video in reply)