diagnosis over the internet is kinda like it is over the phone. Take a plug out now that you have run it a little and see what it looks like, and recheck the gap. I see what looks like a fairly new brake booster on it. I would make sure all vacuum lines are routed right, on top of changing the wires. Soooo many things it could be, has the car been sitting for a long time? What kind of miles on motor? Any mods done to it recently?