THANK YOU for pointing that out! I had it in my mind that both were 40".
I'm glad you found out before going. Right now we're on the "get bigger for Grizzly" diet, well, at least my 4 year old is.
He refuses Soarin' (though next time he might go, b/c we watched the Bonus Features of Aladdin and it has a game that has a part that's kind of like Soarin' with music and a point of view like you're flying over things and he liked that), refuses Splash, and various other 40"+ rides, but ever since he walked past Grizzly he's just begged to go on.
Last time he was about 1/2" too short, bummer! But the fun part is that when they measured him and he was too short still, they gave him a card that basically says "when you're tall enough come back" and you can get as close to "front of line" as DLR gives normal people. We got one in September for Star Tours, and in December when he'd grown the millimeter he needed (ooh don't get me started on that 2nd measurement) we literally got front of the line access. Were sent through a door with stairs and boom we were right there. Crazy!
But he won't go near Soarin' to get one of those cards, LOL.
Oh, and if the 3 y.o. is upset about being too short for Grizzly, if a parent takes her over to the redwood play area, be warned that there are TWO 42" requirement parts there. One is a tire swing and the other is a rock climbing thing. The tire swing was right out b/c they go alone, but with the rock climbing thing the attendant said that as long as hubby was right with DS, they would let him go on it. Keep in mind though he was something like 41.5 or even closer, not 40", so I can't guarantee the same thing for you.
But as long as you avoid those two areas, there's a lot to play in for littler kids over there, while the other goes on Grizzly with another adult.