Help - 1997 Z71 Trouble codes...

I have been getting a P430 code (cat system low) for over a year. Have replaced all O2 sensors and both cats. Still getting the code as frozen... Just recently I had it scanned and the computer listed p700 and p1100. Both are dealing with tranny control (700) manu. specific power train (1100). I can't believe that the emissions code and the tranny codes are related, but who knows?

I live on a hill and tested the tranny by taking said hill in overdrive, 3,2,and 1. All was fine except in 2 which was very sluggish and had a whirring noise which seems to confirm a tranny control problem.

Two real questions:
1. How to fix the @!@#@#$% emissions system.?!
2. Does the described tranny trouble mean adjustment, or replacement?

Camanohawk:banghead: