emission trouble

This MAY come down to extreme measures. Not familiar with your cam. You may have to yank the cam out, toss a stocker in there, and finda smogger carb.

I think it's preposterous that your state checks vehicles that old

AZ is worse. They require a test of 67 cars, which, unless they were built and sold for CA in 66-67, NEVER HAD any engine emissions controls

Might be easier to pick up a used "good shape" stock 318 and swap it in there for the test, LOL