White is not necesarily bad .. grey does mean things are really hot..
So, do you see signs of definate overheating:
Use good magnification and good lighting..
on the porcelain insulator .. see any tiny black spots or spots of aluminum stuck to it? does the surface appear crazed rather than smooth?
look at the edges of the electrodes.. are the sharp, square edges rounded over (melted)?
Look where the center electrode meets the insulator.. There's a type of cement holding it in there.. this cement will "boil" if it's too hot.. the result looks like cement is coming out.
BTW..we're talking about using and examining a brand new plug for the chop.. an old plug is useless.. it has history.
check timing .. too advanced will mimic a hot, lean mix.. So will too-high compression ratio. There are other things that cause what appears to be a too-lean condition.
But hot and lean is where the power is. If it's not too hot, you're ok.