Well I finally got it.

I used plugs with a smooth insulator and it worked fine on all except #7. It appears that the dialectric grease I used on the plug to boot interface created an air lock seal and kept pushing the boot off.

It appears that the flexible insulator does not give a rigid enough path to push the red rubber boot on all the way and it is just short enough to keep the spark plug clip from making contact with the spark plug before the upper boot on the rocker arm cover contacts the rocker arm cover. Probably manufacturing tolerences or cheapness on the vendor.

I finally had to go buy 1 ribbed spark plug and put it in that cylinder. Then with some extra downward pressure on the rocker arm cover boot it is now down and connected.

What a PIA. No more smooth insulators for me.