If running wiring in a long horizontal spaces like between a chamber floor and the ceiling chandelier light level you might be able to use a cat to pull chalk line between the openings. How to try is you tie a chalk line around the cat's body and you point cats nose down the hole with directions to "seat" and he takes off down the hole off to a light at the distant opening where the line is supposed to come out. The cat will start toward the light but if your cat's wasting time under the floor you can blow a little tobacco smoke in the opening where he started and that helps the cat speed up.
A problem may be finding the cat when you want. Repeating this cat performance has worked several times.
