the pinion shaft that the spiders are on eggs out in the carrier housing causing that play. Most of the time, the gears are fine, you just need a new carrier. good time for a locker or spool.

I doubt it's a T&D problem or failures would be random cylinders. IDK, maybe a valve guide or stem issue.

here you go.

https://bangshift.com/general-news/tech-stories/is-the-factory-wrong-about-which-oil-you-should-run-in-your-late-model-car-stop-following-oem-oil-advice-the-recent-gm-recall-proves-why/

used to do my boss 302 solid cam that way.

Most fords use a resistor wire from the ignition switch to the positive side of the coil that I've had go bad. Make sure that you have the proper voltage on the coil. Also make sure the coil isn't connected backwards ( - side goes to the points). Lastly don't overlook a bad ignition switch. You can always hot wire 12v to the + side of the coil and see if that fixes the miss, but it will be hard on the points so you might want to put an old set in to try.

This was last night. Only second time that I saw it in central PA. Last time was mid 80s and wasn't near as nice.

awesome! Explains all those 120 mph rides in the old mans 59 Buick convertible as a small kid with mom just a bitchin. Wonder what those guys would think of the Nascar of today.