Totally do-able. We took baby at 6 mon to
Disneyland - cross county! and he was perfectly fine.
We went with no expectations, just that he wouldn't be able to ride much and we would have to do lots of baby swaps. We used lots of sunscreen ( I like California Baby) and used light linen swaddle clothes to help block out sun in the stroller (we have a Britax, with a large canopy, but I wanted to make sure.)
Baby centers - use them and often!! Nice places, very cool and relaxing. Breastfeeding? Whip it out!

I've breast-fed at the Blue Bayou, Finding Nemo, Haunted Mansion, Peter Pan, monorail - name a ride, I've done it. Because when baby is hungry, he makes it known! (Get a linen cloth - they were so useful - nursing blankets, suncovers, light blankets - everything!)
Rides that he liked at that age: Peter Pan, Mansion, Pirates, Small world - anything speedy and smooth. I did not take him on Dumbo though - I didn't feel safe till he was officially 1.
All the hotels have pac&plays, and that's where he slept. Mostly we co-slept till he was solidly down and then I would move him over. He got so tired that he went to bed easy. (yet he still gets up at 7am. How?)
One trick that I was taught w/regards to B/f: tickle their little hands. It made my guy nurse more. Plus, nursing on the airplane is a lifesaver. I used my travel bobby, and it worked very well for that. Slings or mei teis are great for when you go on rides. That's how he rode Pirates - the sling helped me keep a tight grip on him.
Good luck and have fun!!!