Last year after running the full we had massages at BWI promptly following the marathon (2pm?). My sister who is a massage therapist and also finisher of many marathons suggested that we get a massage the day of the race.
I made the reservations far in advance of the race, so makes sure you call ASAP!! They were completely booked Sunday and Monday following the marathon.
The therapist I got was hesitant to massage my legs at all. I would call it "light" touch

She did not do alot of stretching, either. I have only had 3-4 professional massages but I must say I was disappointed in what I got that day. I just don't think she was well versed on "sports" massages--she seemed horrified that I was having a massage after running a marathon. Of course, I completely understood her rationale for not doing much on my legs but it is not what I wanted, at all. We did the 60 min massages.
Now, do I think it helped me recover?? YES YES YES!!! Even though it wasn't exactly what I *thought* I wanted I know it helped me recover more quickly. Last week after an 18 mile training race I was much more sore than after the marathon last year! Actually, I wasn't really sore after the marathon, at all. I was sick as a dog--but not sore

(I got a stomach virus after running the marathon)
Personally, if I were attempting the Goofy I might contemplate a 30 min massage after the half on Saturday. Even just a quickie w/ the therapists set up in the tents at the finish line might assist your efforts for a smoother run on Sunday
forgot...I might call SSR on Saturday or Sunday and put in a request for a massage therapist that has good sports knowledge. From what I understand the massage therapists work at all the resorts-just get randomly assigned. (I believe most of the Deluxe resorts along w/ SSR offer massages) They all work for a spa company that Disney must have a contract with.