Originally Posted by Andyvh1959
As such I can legally use it as a 1956 vehicle relative to emissions.


No, you cannot legally do that. The federal emissions laws are related to the date of manufacture for EITHER the vehicle, or the engine, whichever is newer. Legally, you'd be required to meet 2001 emissions, all of them, including vapor capture. The feds have been cracking down, hard, of late. It's trickling down to the hoobyist level.