The silver/graphite above is mine. I too chose to apply it myself for $125 instead of paying $500 for a professional to do it. With patience you can do a REALLY good job yourself. I took mine back to the vinyl supplier/installer after I did it myself and he said he couldn't have done it better himself. Other than knowing a few tricks, there's no magic to it.
Definitely NO CLEAR. The beauty of vinyl is you can change in on a whim. When rocks chip it up or you're tired of it, just peel it off and apply new. But this stuff lasts many years and takes a quite a bit of work to get off. Me saying "just peel it off" may be an understatement
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As for the NACA duct and rear license plate area..... it's personal preference. They are both VERY difficult to do in vinyl and I personally like the stripes going around the NACA duct. It really accentuates the opening. I made it a point to NOT piece-meal my stripes like the previous owner had done on my car. At every difficult spot (bumpers primarily) they had cut and used two pieces. So when you look close, there were seams in the vinyl in many spots. So as said above, the radius around the bumpers are the worst pieces. I think it looks pretty nice NOT going through the lic. plate. Just my $.02