So here is an update. Just to review what has been done. I initially had a windage tray spacing issue and we fixed that issue. I have replaced the rockers, push rods and lifters. We verified timing, re-checked the vacuum lines, there are no exhaust leaks. A compression check was done and it read 150 on each cylinder. We took off the heads and had them inspected at a quality speed shop and everything came back good. I think the only thing that hasn't been replaced is the flexplate. I purchased a new one and sent it to Paul. He balanced it and I'm hoping to install the new one soon. I'm hoping this is the problem. Here is a video of the car running while on the lift.
https://www.youtube.com/watch?v=h0Ps-O3EODY