Needs more context for me. Is “G-men”, like the old slang for FBI agents, a common slang term for the NY Giants? Not one I’ve heard, but I’m no expert.
Yup, although “big blue” is more common. For example, one of the fan sites is https://gmenhq.com/.
What state is this exemplar of efficiency? I remember when it took New York nearly that long to make mine, but that was back in 1986.
Or maybe they couldn’t fit an “N” between the 3 and P. 
Stuck behind E SEAN with police supporter specialty plates who couldn’t figure out how to get out of the parking garage today when I was leaving work.
On the back of a BMW X5: DEMI BMR
The driver didn’t look particularly short.
California. I finally got it.
Silly plate, HTTP 202 = request accepted for processing
Saw this morning: ZMBKLR1
But what is a “Zimbuckler”? I know what a “swashbuckler” is.
You’re kidding, right?
Honestly, I don’t get that one, either.
Not even a little bit.
That is totally 100% opaque to me. And I’m not going to google. I’m expecting the poster to come back and explain themselves adequately to their audience.
Zombie killer?
Zamboni collar?
That seems likely, now that I look at it after you suggested that, but it whooshed me big-time at first.
Yeah, I thought that was rather obvious. But obviously not!
I too thought Zombie Killer, although it was a little obscure.
Depends on how top-of-mind zombies are for any observer. In my case, not at all. Oops. That is one of those “How could I have missed it?” 
cases.
Zombies might be more prevalent than you realize!
With all the Florida Men (and Women) around here, I’m not sure they could find a steady diet of Braaaaiiiinnnnnzzzzz! They might well all starve or migrate elsewhere. But it’s long slow shamble all the way to the GA border, and not too many Braaaaiiiinnnnnzzzzz! to be had much past there either.
Florida: where the livin’ is easy and the zombiein’ is rough.