Have I De-masc-u-lated Myself?
I think it falls into the "so uncool it's twice as cool" category- and, incidentally, is damn close to my dream Mopar.
Definitely keep it stock- we're talking about the SLANT SIX here, man! They may not be much for tirefrying, but will acheive interstellar level mileage figures as long as their caretakers keep the crankcases 3 or 4 quarts full of some kind of petroleum lubricant. Hell, a millenium after the Apocalypse, roving bands of mutant cockroachoids will battle each other under nuclear winter skies for territory, driving slant-powered Darts and Volvo 240s- that's not badass cool? Of course it is!
I like the Army Staff Car idea, but I think you should hold out for a WWII-era car to give that treatment to..