0.00 (no resistance, same reading you would get if you connected the ohm meter's leads together) would strongly suggest a shorted primary. No resistance as in "open-line" would imply an internal break in the primary winding; either way (if your meter is trustworthy) you have a problem.
I assume that you are using this coil in conjunction with some form of electronic ignition? If so it may be injured; as your coil degraded (shorted) the resistance went to zero, while doing so current flow in your EL went up, beyond 5 amps is like giving your unit the "electric chair". If your coil opened then the 400+ volt EL discharge to the primary windings would have been reflected back to the EL unit, which it won't tolerate for long; hard to say how long.
If you still have the 6 volt coils and the ballast resistor laying around you can test the EL unit by insuring that you have 3 to 5 ohms of combine primary resistance; connect the single coil up to the EL and kick away with grounded spark plug, if you have a Tri-Spark you hold the self test button in and then turn the ignition key on, if the EL is good you'll see a shower of sparks. If you have some other EL then kick away.
Best wishes!
