I've got about a decade on you, in years, and I'm not yet a year on T. I'm lucky to pass 100% of the time, but there are those odd moments that I realize, like you said, that I'm passing as a much younger guy. There's a group of (I swear they gotta be) junior high-high school girls who must LIVE at the mall in my town, because they're there every time I go in, trying to make conversation and being flirty. I've got a kid in the seventh grade. It's awkward. Last weekend I went into the big liquor store in town to get a few four-packs of a particular craft beer and the kid at the register (I know he's only about 23 because I was in there once with a friend, pre-t, and he gave his age in conversation) looks at me and says, "okay, kid, let me see your ID." Geez. Alright. That's the way we're going to play?
There's not much you can do, or much that I've found to do, other than dress impeccably and be man enough to laugh it off. Your job strips you of dress, which sucks, but the confidence you'll gain by looking sharp and being taken more seriously in your everyday life will pay off when you're standing there being talked down to by some ->-bleeped-<- who's got something to prove, and is bound and determined to attempt to prove it at your expense. Also: don't be tempted to let the dirt-stache grow hoping it'll look like stubble. It never does.