IPADave
Turning a whiter shade of pale.
Couple things--having done professional catering (in a past life), unless you are feeding a softball tournament or sports banquet full of "bruisers", your estimates of portion sizes are about twice what they need to be. 4-6 oz meat per person and 2-3 oz side per person is more in line--grandma is only going to take 1 piece of chicken and two tablespoons full of potato salad--you get the idea. Also, not everyone is going to eat a portion of every item--so for a head count of 90-100 ppl, all you need is a max of 50-60 portions of each item. If you do a full 90-100 portions of every item on the menu, you are going to have a truckload of food left over and wasted a lot of money up-front. Depending on the batch size for your BBQ sauce, you may be over-estimating that as well--16-24 oz sauce per 10 lbs of cooked pork is more than adequate--you want the flavor, but you don't want a soupy mess that will mess up peoples clothes--you do not want to be serving sloppy joes--remember, people are going to be walking around with this stuff and socializing, not sitting at a dining room table.
I concur that you will probably need to rotate racks to cook the pork more evenly, but not everything has to be finished at the same time. My experience with graduation parties is that people straggle in and out over the course of hours, not all at once--so you want a fair amount done and out on the tables to start with, but you want your back-ups "staggered" to put out fresh food at intervals over the course of the time-frame you are working with. If it is all done at the beginning of the event, it will be dead by the time the last guest arrives.
As a matter of food safety--hot food needs to stay hot and cold food needs to stay cold, so put out small batches and replenish. For mayo-based and egg-containing foods like potato salads and pasta salads, or cole slaw, you want to "double bowl" them--place a larger bowl or pan underneath the bowl containing the food filled with ice to keep it cold--besides--who likes the taste of those foods at room temp anyways?
Just a few tips from someone who has done this before--hope it helps.
Good Luck!!!
That's some great information. Thanks for sharing!
-Dave