Hi! Mom to an Aspie age 6 and an NT, age 3. We do WDW twice a year and the most recent trip was the first one after the DX of Aspergers.
suggestions:
Pace yourself. I think the best thing (besides the GAC) was that we followed my son's cues for this trip. Instead of trying to fit in as much as we could, when we started to see the overload, we packed it in. We also had a couple of mornings where we just spent casual time at the resort pool (or whale, in the case at AS Movies). We got so much more pleasure out of this trip. BTW, I did a trip report for mouseplanet...PM me if you'd like to read it, and I'll give you the exact URL (don't know if I should post it here).
As much as my kids love the Disney transportation (we ride the monorail back to our starting point several times each trip), we've found that our car is much better for getting away quicker and calming the meltdowns.
Rent the stroller. I don't care if my son is 13, the stroller really calms him down, partly because the sides and back block out a lot of stimuli. It's also great because fatigue triggers those meltdowns! If it weren't for the conservation station at AK, we never would have come upon this wonderful lifesaver.
Sit down meals are great for dietary restrictions. You can call ahead when making the priority seatings. My son has a problem with food dyes, and I've called ahead with no problems. It just requires a little more planning of your day, but the rewards are definitely worth it. Plus, your son will look forward to where the meal is, since he knows. Mine are begging for 'Ohana already!
We bought a refrigerated cooler at
WalMart prior to our last trip, just under 85 bucks. My kids are yogurt fiends, and to have the yogurt, fruit, cheese and lovely beverages for mom and dad after the kids went to bed made it worthwhile. If lugging a cooler is not feasible, rent one at your resort for the 10 bucks a night. You can keep your son's diet while on vacation.
Any other questions, feel free to ask.
Suzanne