Are you under a canopy or in a trailer or what? Asuming you are under a canopy see if they will let you use chafers to hot hold your pulled pork. As for slaw I'd break it down in to 4oz Styrofoam containers in a refrig if possible. How ever you do it you need to be able to maintain proper temps.
Figure out how many people will be there and cook for 10% of that Example - if they expect 1000 then cook enough for 100. If you make through the day ok then grow from there. Good Luck