Misfiring all of a Sudden
To close this thread, several things I think led to my misfire.
1. I had recently disconnected the OSAC valve. I completely forgot to cap the carburetor line, so I had a small vacuum leak there for the past month or so, which may have contributed to the problem.
2. I went ahead and installed a new Echlin Napa brand PCV. Kept the old (original Chrysler stamped) one as a spare in the trunk.
3. New spark plug wire.
so far so good, thanks for the help guys.