Actually, I think it's a great idea. My toy is currently metallic grey. When I get around to paint, the roof is going to be white down to the drip rails.
Practical experience: The roof on the 7118 truck is half white/half red.
You can put your hand on the inside of the roof(no headliner) and feel the temp change where the white paint ends.
the clear coat and most of the black paint is gone on the hood and roof. it's now a combo of flat black and bare metal now thanks to the tahoe sun. I thought about doing the hood as well, but I'm not sure about the glare.
As far as the hood goes, I don't notice a problem with glare on my stocker(I think I get as much sun as you do ) but I don't know how it would look. I think white hood/black fenders would look like you replaced the hood and didn't bother to repaint) If you have really bad fade/peeling, you might consider doing the center panels or maybe the whole hood in semigloss or flat black to cut down on the glare and still protect the metal. There are a couple threads on just painting the raised flat panels on the hood flat. They turn out looking pretty good.
I want to use adhesive vinyl, like what you use for racing stripes. It would be removable, but would work just as well. No need to cover the whole roof, just lay down stripes between the rub strips.
No overspray, no fumes, no mess.