On the way home from work today the left cylinder stopped firing.

Got Black Beauty home ok, and pulled the plug & tested for fire....and found no glory. Swapped the plug wire from the right side....and got lightning. I Definitely have a coil issue at this point.
I read thru this thread thinkin I might have a similar issue, all the wire connections are untouched at this point. I'm thinkin the CDI is toast from the 1500 mi run to the Midwest rally & back and 100+ heat for the first 3 days of the trip.
Any suggestions on what / how to check the CDI?
