Rust Bucket,
thanks, and now it makes sense. The smaller bushing is sized to be line honed when lined up with the rest of the housing.
Oh another little tid bit: I was talking to a rebuilder a while ago. He was explaining to me why he charges so much money to rebuild one. He told me that sometimes when there is a little wear on the shaft, he will chrome the end some to bring the size up a bit. Neat trick I think.