I know in California, there is big plaque in most of the shops that reads "Tempering with smog equipment can result in fine of 1000 dollars". One of the shops that did my exhaust work on the VW I've had a while ago, fabbed up and installed a turbo kit, and did a full offroad exhaust with a dumped external wastegate. Moral of the story is, if you know the techs or the owner of the shop, you can do just about everything.