I think I found part of the problem. At least I found A problem.
I did the juicebox ignition upgrade last night. Although the wires and dist cap appeared to be pretty new, the wires were Mopar units dated 1999. The plugs were Bosch coppers, installed back in 2007 and have 25,000 miles on them. considering the miles, they were surprisingly clean and none of them were showing any signs of oil burning which surprised me for a 172k motor.
When I pulled the plug wires off the dist, cylinder #4 terminal came off with a puff of blue powder erupted from under the boot. The picture below says it all. I'm amazed it ran as good as it did, once it got warmed up it wasn't missing at all.
It still runs a little rough when it's cold but I think that's just the BBD being a BBD. If I get up the motivation I'll take it apart and clean the idle tubes and see if that helps.