Tom, your numbers for cooked meats are about right...4/10lb per person for PP...5oz or 1/3lb is about the standard most folks go with, so 4/10lb should give a bit of extra. The chix thigh/PP combo is a good number as well, and gives a bit extra if most would like a thigh and a sandwich.
For sides, figure 1/3lb as well, so if you have a coleslaw recipe which uses lb measures, you can adjust easily. If it's cup measures, figure on loosely chopped coleslaw weighing 7oz/cup, not 8, then if 1oz wet ingredients are added per cup, you'll have 1/2lb per cup. Anyway, go for about 33-35lbs per 100. Beans, if canned, go by the weight on the can plus whatever you use to modify them (such as Dutch's recipe). If you buy food service size cans, the 7lb-5oz can (un-modified) should be enough for 22 people, so if heavily modified, 4 cans would be about the right amount (not everyone likes beans due to flatulence...LOL!!!).
Buns or rolls...at least 100, but I'd shoot for an extra 20%, just in case someone wants their thigh as a sandwich (excellent way to eat yard bird, IMHO). You may want to have an assortment of whole-wheat, white, sourdough, onion, etc, for varied tastes...they'd love you for giving them a bit more personal touch like that.
Have you got drinks covered? Non-alcoholic, I presume? (most companies don't allow it on premisis is why I mentioned it). Iced tea goes well most of the time, but depends on the weather this time of year...rainy season started here right now, so probably some hot drinks and cold drinks, but, you're in Florida, so cold probably works for any occasion.
OK, so, 1/3lb per person for meat, 2 sides and a dinner roll/bun for each (with a few % extra), plus beverages.
Have you enough cooker space? Doing some smoked and some grilled? Are you cooking ahead and reheating in roaster ovens/crock pots? Do you have enough fridge space for prepared sides and raw or pre-cooked meats? Just some things I consider every time I plan an event. Don't forget coolers and ice as a back-up for refer space...just be sure everything will stay dry.
I think that covers most everything...doing all of the meal is a big chore, so breaking it down by task and food type will help keep it from becoming so overwhelming. Also, ask someone for a bit of help with coleslaw or potato salad prep...that's labor intensive work getting those ready. Canned beans are easy and pretty quick to modify for a bit of extra twist, so don't sweat the beans much.
It can be done, especially with a littlew help on the sides prep...planned a 2-day, 6-meal family reunion a couple years back, and after seeing it all on the computer monitor, right down to the cooker space I would need, and when I would need it, and what would be tied up...sometimes that's the only way to be able to visualize it. Write up a plan if you think cooker space may be an issue, and then you'll be able to decide if any changes are needed.
Eric