'83 with recently rebuilt 22R failed emissions with high CO. 70.4311 gpm and the limit is 65. The note on the form says that's usually due to the mixture being too rich. I figured I might as well change the plugs, cap, rotor, wires and air filter while I'm at it. The oil is new. Should I try the tune-up and have it tested before monkeying with the mixture? Is there anything special I should know about this engine/carb regarding emissions? I've never had a vehicle fail emissions so I'm new to this.