[Daves55Sedan]

That plug probably has a square recess on top, or maybe it is a hex key recess, but I doubt it. Probably square. See if you can find a piece of 1/4 inch square bar stock and stick it in there. If that fits, you can take a little 1/4" open-end wrench and turn that plug in. May need to fiddle around with different sizes to get the right one.