The Smith-Jones-Robinson Classic

On a train, Smith, Robinson and Jones are the fireman, brakeman, and engineer, but NOT respectively. Also aboard the train are three businessmen who have the same names: a Mr. Smith, a Mr. Robinson, and a Mr. Jones. Who is the engineer?

1. Mr. Robinson lives in Detroit.
2. The brakeman lives exactly half way between Chicago and Detroit.
3. Mr. Jones earns exactly $20,000 per year.
4. The brakeman's nearest neighbor, one of the passengers, earns exactly three times as much as the brakeman.
5. Smith beats the fireman at billiards.
6. The passenger whose name is the same as the brakeman's lives in Chicago.

Mystery Master's thoughts on this puzzle: Where everybody lives is not completely clear. Two cities, Chicago and Detroit are given, but the name of the city between them is not, so I called it "Halfway". You also can't pinpoint where everybody lives, so I force each person to live in one of the three cities. Therefore, in clue (4), I took the brakeman's neighbor to be somebody who lives in his city. For clues (3) and (4), I took into account that $20,000 is not exactly divisible by 3 ($6,666.66...).