One way to find out what kind of smog equipment your truck came with is to find the RPO emissions package code in your glove box, if it still has the RPO code data sheet located in the glove box. If you can get the RPO emissions package code, then take it to a Chevrolet dealer parts counter. The guy behind the counter, will be able to give you a copy of an exploded view of all the smog eqiupment your truck came with.
I live in Nevada, and in most counties you will still have to get an emissions inspection. The only places in Nevada, which have no emissions inspection currently are rural areas way out in the midlle of "bum f*cked Egypt", and with so many ******, liberal, tree hugging, communist, lawyers coming out here to Nevada from California, and getting elected to positions of Government, it will not be long before emission testing will be mandatory across the entire state of Nevada.
The good thing about Nevada emission testing is that the visual inspection is minimal. The only thing they will look for on your truck has a smog pump, and an EGR. They will not even look to see if it is hooked up and fuctional. As long as they see one, it passes visual.
Another thing you can do here in Nevada is register your truck as a "Classic". If your vehicle is 20 years or older. All that is required is one emmissions test upon registration, and that is the last time you have to test it ever again. The only restriction is that you are only able to drive the vehicle no more than 2500 a year.
California on the other hand are a bunch on Nazi's. They will look to make sure you have an EVAP, Smog pump, EGR, all proper vacuum delays, hot gas recirculator, stove pipe, and make sure you have no non-CARB legal aftermarket parts on it. And then on top of that they will do a functional test on the timing, EGR, EVAP, and smog pump diverter valve. California sucks anymore! That is why I moved away from there.