There was not a single certification from Carb on mine. They looked at it and said "yep, it is all propane now" Done.. BTW, you pretty much had to pull the fuel tank as well.
kind of a primer on the rules in NV
http://www.dmvnv.com/pdfforms/ecgas.pdf
and the bible
http://www.dmvnv.com/pdfforms/mc036.pdf
Looks like Cali still requires a smog check
21.065Propane (LPG) or Natural Gas (LNG) Conversion
A smog certification is required for original registration, transfer, and biennial renewal of a vehicle converted to liquid propane gas (LPG), liquid natural gas (LNG), or compressed natural gas (CNG). Conversion may be complete or dual with gas.
EXCEPTION: The Bureau of Automotive Repair (BAR) exempts heavy-duty vehicles weighing 14,001 pounds or more GVWR (gross vehicle weight rating) powered by natural gas (fuel code “N”) from all smog certification requirements.