Originally Posted by B17
3. (minor) It's probably easier to buy a track crank and matching BB than it is to find the BB that will give your non-track crank the chainline with the ring on the outside.
103mm bottom bracket +/- 1 spacer ring seems to be the ticket for the outside position to line up nicely with a 120mm hub. sugino makes a nice square taper one.
Also, a 1/8" 130 bcd track ring fits on a road crankset just fine.
Hard to find a 1/8" 110 bcd ring, though.