FastWS6-LS1

I've had some pretty bad luck lately with my power steering system. When I originally bought my 180,000+ mi. 2002 Trans Am WS6, it had a bad leak in the original power steering rack. Rebuild kits were not available for that specific rack, so I replaced it with a remanufactured unit from O'Reilly's. That one didn't hold up long before the bottom pinion seal blew out. That was about the same time I upgraded to a new pump assy. from Turn One. Power steering kind of worked, as long as I kept fluid in the reservoir. The leak got so bad that it would empty the reservoir once a day! I took the rack back to O'Reilly's and exchanged it. The next one they gave me did not work at all with the pump. When I hooked it up, it did not flow any fluid through the rack, like it was plugged up. I ended up burning up my new pump within minutes and had to exchange it. I now have the replacement pump, but now I went yesterday to exchange the rack for another one. At that moment, I noticed there appears to be some sort of check valve thing in the pressure port on the MasterPro rack. The replacement rack I got last night has the exact same thing. I'm wondering now if that's what's blocking the flow. Do I need it there? Do the OEM racks have one there, or no? Should I remove it? I've already replaced the pressure line with a new one, and have verified the return line flows freely. The blockage appears to be in the rack itself. Any advice? I need to get this back together tonight to make it to the drag strip tomorrow. Any help is much appreciated!