[jeepmor]

Battery was dead this morning, replaced it, problem appears gone after hitting high revs and not getting the CEL/P0301 anymore. Got 8 years out of an Optima Redtop, not bad. Looks like this is the fix, it definitely wasn't the coil swap. Haven't reproduced the CEL or code after revving into the 7k range that triggered the P0301 initially.

Will label old coil good and keep it. Considering the wrestling match getting them in an out, the new coil can stay put. I'll need to test more with some high revs on the commute home tonight, but so far it looks like the battery was the root cause since I can't reproduce the misfire.

BTW, O'Reilly's carries Size 35 Optima batteries and I was able to find one on the shelf quickly. 10 minutes to swap out and so much easier than exchanging out those coil packs.

PM update - fix appears solid, hit the 7k plus mark several times coming home, no CEL. Looking back, there was a real sluggish feel out driving before the battery died the next morning. It never threw a battery light. Hope this helps others troubleshoot. I have a DVM, but never checked the battery voltage to be honest. At my mileage, I figured the coil unit was kaput.

On topic of upgrades in regards to the OP, I no longer plan to do them if this still works fine. I was ready to upgrade the whole system, but when the new coil pack didn't fix it, knew I had something else to look for. I'd have chased my tail on this for a while if the battery hadn't just flat died on me. It's demise and the commute to work had me reviewing a few signs I should have caught, namely the loss of power. Now it's pretty snappy again and pulls down low better. I need to install a voltmeter, wouldn't have been any surprises that way.