Mopar 360 noise PLEASE HELP

Hey guys I just recently got this truck running and driving after sitting for 25 years. About a week ago it started to make a strange noise that’s sounds like a loud buzzing/grinding and I believe it’s coming from down by the flywheel/converter area, I can only hear it at certain rpms when idling and when the trans is under high rpm’s going down the road. I put a new starter on it thinking that maybe it was catching on the flywheel but had the same result. I’m new to working on stuff like this and I’m at a loss. Theres a video down below. Any ideas would be appreciated. Thanks
77 mopar 360/727 trans

Author: 77powerwagon