There are various types of pop-ups, pre-selling is one idea, it minimizes your risks, but, will likely result in lower sales. There is always a gamble, I would avoid ribs to begin with, or offer more than one meat, so that you can offer alternates if you run out. I suspect you will have to over-cook some. Do a lot of advertising as well.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
Whip It Off, Chambers!
"perhaps...but then again...maybe not..."