High HC's is unburned fuel. High O2 means oxygen not consumed in combustion. CO is low CO2 is low indicating lean/lean misfire combustion problem. Does it run smooth?
A scan tool or WinALDL something you can display datastream will help you diagnose what is going on. You are missing out on pertinent information, fuel trims, input values -ECT, O2, MAP etc. You can find OBD1 GM 12 pin scan tools all over the place. I have several that have inches of dust on them myself so people are always unloading them cheap, look on marketplace or craigslist etc. Don't get just a code reader, you need one that has serial data display. There are many options for this.