Pluto's Process can be found the Walt Disney Treasures "The Complete Pluto" Volume Two DVD.
Pluto's Process is a feature that show some of the steps in making a cartoon. It is broken in up in two parts, A Deconstruction and then the Pencil Test. Both part use the same cartoon "Pluto's Judgemnt Day".
I thought that the Deconstruction part was the better of the two. The Deconstruction splits the screen into three or four part showing the different parts of animation. One or two screen show the pencil drawn backgrounds, one screen show the penciled drawn character and moving parts while the last shows the finished cartoon. The Pencil Test show the whole cartoon in drawn with a pencil.
Watching the pencil test after watching Deconstruction is almost like watching a rerun. You have seen most of it already.