When Downtown Disney first opened, Disney bought orange and yellow double-decker buses from a British manufacturer (I can't remember its name.) and ran them between the Paradise Pier Hotel and the main parking structure.
They're probably still sitting unused somewhere on the property.
They sat in the lower level of the parking structure for the longest time. You could see them on your way to park. Not sure if they're still there, but, I'm sure somebody knows. I sure miss them. They were handy for getting over to Downtown Disney when the lines for the trams were too long.
Yes, 2 of those buses, probably the only 2 they had, sat in the Chip 'n Dale level of the parking structure for years. They are gone now. Either they were moved somewhere else for storage or sold. I never did see them actually running. Probably was not paying attention enough those few brief months they were used back in 2001.
Are the buses similar to the AEC's (Associated Equipment Co.) iconic Red Routemaster double deckers of London?
Not really... They were a little more festive since the top level was open-air and covered by a canopy.
They were larger and somewhat more awkward than the omnibuses on Main Street, U.S.A. But, the company was very pleased with the results since it was able to buy the vehicles off the shelf and for relatively little cost.
Those were beautiful busses -- from the second they were first opened until they were mothballed following 9/11, my wife and I always rode those from M&F to Downtown Disney. That was how we made sure to begin and end our days at the Disneyland Resort. It was a lot more pleasant than standing in lines for the trams.
I do have some old photos of them, however the shots were taken at night with a very old and low quality digital camera. Therefore, the images ended up being just headlights against a black backdrop. We had intended on getting more shots the next time we visited... and then the world changed.
EDIT -- I just remembered, I used to have an article about them somewhere in this mess. They were built by the same company that created the vehicles for Kilamanjaro Safari down in Animal Kingdom. The name escapes me... and the article is probably in the bottom-most box in my "filing system."