1986 Other Ford Models Emissions test failing

So I have a 1986 Bronco II it's 6 cyl. 2.9 liter engine. I have tested 3 times and have failed each time. I have improved each time buy doing general emission replacements. Such as: catylatic converter and muffler (3months ago) MAP Sensor (3months ago) Spark Plugs (2months ago) Oxygen Sensor (2 weeks ago) EGR Valve (1 week ago) PCV Valve and Air Filter ( 1 week ago) gurantee to pass fuel system cleaner (2 days ago)

So I tried to pass again today for the third time and I am so close but out of ideas My CO level at idol is 1.99 and needs to be at 1.2 it's all I have left too pass and i'm just flat out of ideas i'm so close just need to drop that last 0.8 to pass.

Have any ideas? Willing to try anything at this point.