Don;
The way the regs read, is everything 4-years and newer get an exemption along with anything 25 years and older. Okay, lets see, that would mean my car built in 1993 with an engine built in 1965 and registered as a 2001 would be exempt. The other one, built in 2002 the engine 1968 vintage and registered in 2003 would be exempt. How in the world does this logic work? The owners of these vehicles in some cases use technolgy from four decades ago, others modern technolgy capable of passing the existing regulations. This is at best not very thoughtful regulation!