OK, I'll show you how spotty my knowledge is of cars... I can R&R an intake manifold and tranny, but I don't know the answer to this question.

What part of the plug should one look at when determining if they need replaced?

Just the tip part, the electrode? Or does the top ring of the plug, from which the tip comes out, need to be looked at as well?

The reason I ask is, my plug tips look GREAT, I mean a perfect tan color with no specks... but the ring around the top looks like it has pieces missing in some spots. I can't tell if it's carbon buildup or if little bits of that metal have been removed.

Should this top ring be completely smooth? If it's not, does that point to detonation?

Thanks.

 

Sounds like your plugs look good, since you have gone to the trouble of pulling the plugs, you might as well change them.