need a better angle to see more on those plugs.
You need to look at a minimum of 3 things when you pull them, heres an example:
1.) the curved ground strap, is it burned back past the curve or is it 2 distint colors getting darker as it gets closer to the edge of the threaded housing
2.) center electrode core, it needs to be silver just on the outside edge if you want just a bit of temp drop safety in it. If its silver all the way across your spot on for that temp.
3.) center ceramic core should be tan to a light tan, after a bit youll see a distinct smoke ring appear about half way down on it going to a lighter color further up in the plug-this means your in the sweet spot.