failed emisions

1990 cady fleetwood base model first test
hc:0.6
co:27.2
nox:2.67

replaced spark plugs, wires, map sensor, pcv valve, engine temp sensor, throttle position sensor, oxygen sensor, cleaned throttle body, and replaced worn vacuum lines

got emissions down to
hc:0.61
co:20.95
nox:2.67

i needed to get them under these numbers
hc:1.0
co:12.0
nox:2.5

i dont know where to look im not good with emissions any suggestions

I am no huge expert on emissions either. But I suspect since the HC are within limits your engine is burning the fuel efficiently.

The high CO indicates a catalytic converter that is not functioning properly and the high NO means your EGR system may not be working properly.

How old are the catalytic converters on this car?
See http://www.catalyticconverterwarehouse.com
Make sure car is at normal operating temp, when doing the emission test.

if the cat is bad it is not plugged up but i would bet it is original equipment

what all is part of the EGR system I know the Egr valve was replaced last year

does anyone know 1) how to tell if that cat needs to be replaced and 2) where i can get a vacuum tube diagram to just go ahead and replace all the vacuum lines

thanks for the help so far

Egr is a system that directs some exhaust gas into the combustion chamber this reduces nox, the cat also helps in this process, make sure the egr works.

OBDII systems has a down stream H02 sensor to tell the ECU/PCU if the catalytic converter is working, however if plugged it doesn't.
Your car has OBDI system,
Any muffler shop should beable to test your catalytic converters.