At least now, all I'm getting is coolant no real garbage or sediment. I found if you pump compressed air through the upper radiator hose It seems to help push stuff out the bottom.
I had to send my cold case radiator back. The core was too thick with the space that I have available. So I doubled down and bought a Griffin. Their core is the thickness I need and the tube thickness I need. But I may still have to cut the brackets off and retig. I guess I'll find out tomorrow when it gets here.