Ron ,
They have the emissions testing here and I have been thru it twice (every other year), both times it was easy. They have also always commented that my truck is so "clean". On the ppm the max is 10 and my truck only blows a . 1, which is as low as the machine measures. They never look under the truck (thank goodness), and really just look that the VIN matches the registration, and for some reason look at the fuel cap?
Also when they conduct the test, they keep me in the cab and the truck is just sitting there idling. I give them $20. 00 and move on.