Nopalito does not take reservations however you can call an hour or so before you show up to be put on the waitlist.
I've never had to wait long.
If I recall, we showed up for an early dinner on a Sunday expecting to wait and didn't have to. Worth any wait if you have the time though.
They don't take reservations, but there is fairly fast table turnover at lunch time
I used OpenTable. It was efficient.
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