Mike. Welcome back!
Do you have a scanner? I ask because it might be a good idea to do a closed loop scan @ idle to see if the O2's are getting lazy....along with seeing the fuel numbers and a few other data items.
Did you add a big bottle of techron to the fuel? That helps me pass the NYS smog inspection.
Off the top of my head, how are the coils and wires, PCV's? I hate to start guessing.
One thing is the CATs must be hot, if they do these tests with cold cats we don't fare so well.
Tom