It's not like Universal where there are some rides you just can't go on (like the Hogwarts ride) if you're too big.
This is a good tip for Radiator Springs Racers and Indiana Jones also. If you have wider hips, grab the seatbelt before you sit down on those as well.It depends on your shape, but I'm on the smaller side of plus size (18w pants size) and I have never had an issue. Goofy's Sky School, as others have said, can be a tight fit. I was able to ride, but bruised my leg. Matterhorn can be a trick but if you just pull the seatbelt up before you sit down, it's usually fine.
For Pooh, sit in the front row for more knee room.I have some issues with being tall (6’5”). Knees have to be cocked to the side on many rides. Haunted mansion my head has to be tilted to one side to fit. GSS is the hardest to get in and most uncomfortable to ride. Second is Pooh ride.
I'm 6' 3" used to be about 400, first time I went to DL at that weight was April 2018, then I could ride everything in the park except Space Mountain, and even then I could get in the ride but it felt tight, turns out I didn't know of the leg cross method which changed everything.
since then I am down about 60 lb and have visited DL on 2 separate 10 day trips (Oct 2018/Feb 2019)
I can fit on everything, leg cross method makes Space Mountain a breeze now.
Also I am sure you know pull the seatbelt out first and buckle it before sitting it on any ride (Indy, Star Tours, Guardians,matterhorn)
For Radiator Springs for some reason people say to sit in the back, no, sit in the front FOR SURE.
As for matterhorn, only sit in the front, and if you arent tall you will have no issues, I used to HATE matterhorn, even crossing my legs my knees still were even with vehicle opening and it banged my knees up SO BAD i couldn't walk comfortably after.
This past trip I discovered if you are tall and you do cross your legs you can slide your body down a bit and your knees can get inside the vehicle comfortably and then you have a bunch more room vs sitting up straight with your legs against your chest.
It's really hard to explain in text.
Either way hope that helps
Sometimes it isn’t the ride vehicles that are an issue. The lines in Fantasyland have turnstiles in them that can be a tight squeeze. I lift my park bag up on top of the turnstile and turn sideways to go through.
I’m a WDW veteran and have never had an issue fitting on the rides. Going DL Sunday with my son who’s stationed in San Diego. Are the rides at DL plus size friendly?