Having a bit of experience in this area and conversing with the epa engineers and lawyers, they are not looking at race vehicles that still have vin numbers. I believe that this argument is an internet/social media rumor. I may be wrong but with speaking with them, they are not going after the converted street vehicles with vin numbers that are used for race/pulling/dyno queens/etc.
This is a hit on the suppliers, not the end users. they don't have the band width to go after the end users. Cut off the supply and you limit the "problem" just like drugs. There will always be the black market and small local markets, they hit the bigger players and it makes a statement. Scare factor goes a long way for the small businesses in the area as a 50,000,000.00+ fine makes you rethink your business decisions.