I read a lot online and these downstream O2s might calibrate the upstream O2s

I bought a new Downstream O2 and will see this week what hapens. Next is MIL eliminators and GUT the CATs

1999 GREEN Contour SE SPORT Duratec V6, ATX, SUNROOF, 93,000 Miles, P0420 ON&OFF -replaced DS O2 --did not FIX *New TORQUE CONVERTER @ 53,000-Intermittent P1744 *New DASH at 53,000 and New DASH lifted-now using MOLLEY bolts to pull down