Ignition problems I think

Ok im getting desperate.
I bought a rusty dart that ran kinda rough and after fixing a vacuum leak (loose manifold bolts) and turning up the idle a little, it was running better.

I flushed the cooling system, changed the oil, thermostat, spark plugs, spark plug tube seals, plug wires, cap and rotor all in the same sitting. Now the engine will crank but won't start. I am not a professional but I have certainly done these simple things many times on other cars.

So I think something is wrong with the ignition. I'm pretty sure it has been upgraded to electronic. The coil wire that goes to the cap is putting out spark but th spark at the plug seems weak. I have read a lot about changing the ballast resistor but don't know where its located the only module on the firewall is the voltage regulator and I changed it out with no effect.

Bring on the knowledge, what do you think?