Yes this is exactly what I'm dealing with.. My issue is finding a square adaptor to place on top of the ez out. I stripped one of my sockets trying to get it.
Did you use a 6 pt. socket?
I changed the plugs several times on this very engine, and was told by a good mechanic to bring it up to temp, then souse it down with Kroil and let it cool off, then give one good Twist to tighten them then take them out.
Had one blow out, see comment above, even that one was not hard to remove the base following this procedure.