Most I have seen are just a hole through the sheeting, and an appropriate drop to the lighting. If you are concerned about the sharp edges in the hole and are not using BX or other metallic sheath cable, you could drill the holes with a step drill and use male bushings and a female on the other side as protection. Females bushings are readily available in pvc but the male ones I have were metal, likely surplus from a big conduit and lighting job some years ago.
In my own shop, I put the ceiling boxes flush with the finish and placed a duplex receptacle on each one. The lighting is plugged into the outlet with a short pigtail of the appropriate cable type. I did this so we could have the final electrical inspection without needing the fixtures installed.
