I had to much wide open area around the -12 screened pick up fitting inside the rear corner of the pan.
If I would have wanted to make the Thaggard pan work properly, I would just add a round oil containing device, made up like R.I.P.S. and most others do. Even with the trap door on my previous pan, the oil was able to move forward, away from the pick up, un restricted (with out a container around the pick up) which allowed the oil pressure to drop off until the momentium changed again moving the oil rearward toward the pick up fitting.
That pan could be touched up by a welder to work great. I just did not have any oil pan sumping experience when I received it bare, with nothing on the inside...