Quick Question Coil issue or more? (Mopar but not A-body)

I have a 73 D100 with a 318 Daily driver ran fine then parked for a week. Tried starting it this week and no go. Turns out no spark at the plug, so I stat at the plugs and work my way back. I go through plugs, wires, rotor and cap, Elc pickup air gap is on the money @ .008 everything checks out good. Unplug the Coil to cap lead and turn over the motor arcing the lead off my valve cover and get a weak spark.
I've heard of coils going bad but I have never dealt with one. Do they usually just break or fad out?

Thanks
j