[Shotimes] no spark

[-Newmy-]

Hey gang, hope everyone is well.
quick question.
for the last few days, the '90 sho would cut out for about 2 seconds, then go again.
today it died completely, so I checked around under the hood, and found that the wire from my DIS that feeds my 5" monster tach had shorted to ground. I repaired it and drove it for about 3 hours after that.
then about an hour ago, it died completely, never to have spark again. I ran home and threw in another DIS, but to no avail. does the DIS have to be mounted to the plenum  to work properly?
My other option is to try throwing in my spare coil pack to see if that works. Im trying these quickly in order to save the tow home.
any suggestions?
thanks
Curt