i don't really know the particulars of de-smogging your truck but i will mention this:
i have heard of no (zero) cases where smog laws were eliminated after being applied. i have heard of several where they were instituted years, decades, after surrounding areas had them.
going to the true dual exhaust, with dual high flow cats, is something your average smog technician is likely to overlook. a missing AIR injection system is not, it's obvious. i have an 86 blazer that someone else desmogged. if i want to register it legally the parts will probably cost more than the truck is worth. if you do desmog it, keep the parts.
the greater power gain will be from the better airflow of the headers, not the deletion of one belt drive. the air pump is only working while the vehicle is cold and how much power does it take? 5 hp maybe?
