The original names for the three hitchhiking ghosts are The Traveler, The Skeleton and The Prisoner. They are now Phineas, Ezra and Gus.
If you look around the exterior of the Haunted Mansion you will find the tombstones of Erza, Gus and Phineas along with other Haunted Mansion characters. This was added in 2011.
Ezra can be called Ezra Dobbins, Ezra Gasser and Ezra Beane. Gus can be called Gus Gracey, and Phineas can be called Professor Phineas Queeg, Professor Phineas Q. Hackenbush and Professor Phineas Plump (often shortened to Prof. Phineas Plump).
Head to the blog to see which ones!
Paul Frees who was the voice of the Pillsbury Doughboy!