You don't have to run housing all the way back. I never do because I don't like the way it looks and it's hard to find suitable 1 1/8" clamps.

This one is routed the old fashioned way, with a fulcrum clip and a pulley.



This one has a five speed that uses two cables. I treated them like derailer cables using Simplex parts. The difference is in the rear, where I ran housings to a couple of SA 5/8" clamps.