from description posted on your website
My 1987 Buick Grand National ,
the valve cover breathers will definitely fail visual in CA ... you need to revert to stock setup, to pass.
and by "K&N stock air filter", do you mean a K&N replacement in the stock air box? -- which should not be a problem. If it's the large, external K&N cone filter, it will likely fail visual unless K&N has a Calif CARB exemption or "exective order" (I think).