Maybe you're right about the pilot hat actually. I must think that over. The goggles however don't look so bad in my opinion. They somehow resembles shades
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.
I was thinking of some kind of bandanna, cowboy hat or baseball hat but.. those didn't work as well.
About the sign. Well that's the point!
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Those mutants feel so though and bad-ass that they don't give a damn about pissing of the others. In fact they could wear "F*** NCR" jacket, go directly to Shady Sands, look into some cop's eyes, and say "whatya starin' at, punk?" and they will still be ok with that.
How about my nightkin?