Acting like one cylinder firing lean.

Found the missing cylinder #7. Found white corrosion on the plug wire connector at the cap end. Took the cap off to inspect and found corrosion on the rotor contact. Cleaned them up and started the engine. Random shake still there. Was playing with idle screw and when it idle from 800 to 900 rpm it violently shakes alot. I just ordered a Street Demon carb and plan on swapping it with the edelbrock 1406. Hopefully it solves it.