I'm building an F-104 right now and have downloaded a ton of pictures of Starfighters (Google Image Search is your friend). Most of the pics definately show NMF wing tanks. You can see the variation of the different panels of the tanks. A few may be white, hard to tell. At least one pic shows gray tanks, but it's a gate guard so that might not be accurate (may just be corrosion repair).
As far as the wings, it's my understanding that most, if not all, were white on top with the NMF birds (except the YF-104s which appear to have NMF wings). It's not clear to me if they were gray on the bottom or NMF. I have seen recollections of folks that worked around them stating that the undersides of the wings and tail surfaces (maybe both top and bottom) were painted gray as corrosion protection after they had been in service a while. This may be true of the tanks too.
Myself, I'm painting the top of the wings white, the bottoms gray, leaving the tail plane NMF and putting sidewinders on the wingtips. I *know* those were white.