You have a California HD emissions truck, so no cats. Just make sure all the vacuum lines are connected correctly and all the parts on the air cleaner sticker are in place or you will fail. Check the timing too.
FYI look at your fill pipes. They are probably larger diameter than the standard unleaded style as the truck would have run on regular leaded gas back in the day. My '85 K30 is that way. Your gauges probably do not say "Unleaded Fuel Only." Also your emissions tag only says AIR. That's all that's required. You'll notice on mine it says AIR/EGR as mine requires both.
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