Is the backboard going to just sit out in the open? That's not a good idea anywhere, but especially not in a restaurant. I would mount a suitable metal pull box (my favorite size is 24" by 24" by 6") on the wall, and run the conduit(s) up the wall into the ceiling, Alternatively, remove a tile or two, make a 2" knock out in the rear of the pullbox with your Greenlee punch and run the wires through a sleeve in the wall.

Look in the Yellow Pages for "Licensed Electrician" or "Telecommunications Contractor" and you'll probably find someone who will know how to do it for you.

Arthur P. Bloom
"30 years of faithful service...15 years on hold"