Running a shop in California in the days of random roadside smog testing roadblocks made C.A.R.B. (California Air Resources Board) a 4-letter word! We did make a pretty good bit of pocket change converting road draft tubes to closed PCV systems, which was another CARB bright idea. The parts stores stocked conversion kits for most cars, and a universal kit that could be adapted to the oddball cars that didn't justify producing a drop-in setup.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!