[Jamo]

For non-SB100 special construction vehicle registrations, the car is registered based on the year it was built, but it is smogged based on the year of the engine. Two different things. If it was built before 1973, it is exempt from smog testing as with any other vehicle.

My Butler was registered as a 1982, but it needed to be smogged according to 1969 specs for the year of the motor (351C).

SB100 still brings your registration under the special construction provisions, but you receive an exemption from smogging if you get one of the 500 numbers.