One trick you can do with the two tone paint job is that with the dark gray on the bottom you can AVOID doing the final 'perfecting' it stage and just get it to a final wet sand stage.... THEN you go and buy a can of that clear plastic gravel guard coating AND paint the entire lower gray area with the Gravel Guard stuff. This will give you both protection for the paint from road chips AND a shiny clear pliable no maintenance plastic coating protecting the gray.
As for your comment about fearing the 'extra' work that you black area would require... well think of it this way :
a ) you just saved work on how 'perfect' you will have to make the gray area because of the gravel guard coating... and
b ) the black areas are probably not as subject to chips and dents as the lower gray area. The roof should be very easy to to get prepped for black painting ( and after all - who really takes a microscope to check out people's roofs.
The hood would probably be the main area where you would spend the maximum time seeking perfection in the surface... and if the hood is such a disaster that the work inspires fear... well you can probably buy a used hood or a replacement hood that will cut the prep work down quite a bit and not end up costing you an arm or a leg.
OR as another option... DO THE HOOD only in FLAT BLACK. This would give the hood that currently hot 'carbon fiber' type look that you see on many of the 'rice car' racers. The flat paint on the hood would not visually amplify any imperfections.
The other upper areas are probably easy to get up to a 'black prepped' stage... since they are in the most easily accessible areas of the car to work on.
On the topic of that bumblebee yellow & black paint job... I would think that the black should go on the bottom and the flaming yellow go on the upper sections. The lower section in black will lower the appearance of the car and the brilliant yellow on the upper section will stealth the appearance of the car so that when it drives by people, they will not be able to instantly identify it as a Probe. Instead they will say " What the heck was that ? ! ? "...
And just to annoy people, remove all traces of Ford badging off the car just to keep them guessing
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