Embarrassing yes, but I am overweight at 225 pds., 5'4" and I am wondering if I would have trouble sitting in the seat for this attraction. I know Disney makes their rides to accommodate heavier folks.
My dimensions are a bit different than yours. I am 6'3" and 275. The only thing I remember that was uncomfortable about SGE was that the shoulder harness pressed down too hard on my shoulders.
Do you mean Stitch's Great Escape? If so, you shouldn't have any trouble with the seats. I was abler to ride most of the rides with no issues, and I am 270 lbs. Granted I am male, so I might carry my weight differently, but I have more trouble with the airline seats than with the rides at WDW. I simply can't ride Dumbo with another adult, and Snow White's Scary Adventures is a tight fit, but all other rides were at least roomy enough to let me enjoy the ride. I have found that the older the ride, the more likely it is that it is not made to specs for people of my size. I fit fine on Peter Pan, but I often spend the whole ride wondering if my weight will cause the ship to break off, careening towards the miniature city below.