It's a 3-way pilot light with the load at start of run.

The pilot light itself is wired parallel with the load so at the pilot light side there needs to be- 2 travelers + 1 common + 1 neutral. = 4 conductors. What should we pull to that location? It's residential. 12/3 plus one 12/2 and just cap one conductor off?

It has been years since I wired romex in Pa. but I'm picturing a box with a pilot lamp and a 3-way. A 12-2 is coming from my feeder, a 12-2 to the load, and a 12-3 to the other 3-way. I would put black electrical tape on both ends of the white in the 12-3 and that would cover the pole and 2 travelers to the 2nd 3-way, which would come back to the 2 travelers of the 1st 3-way, and the black from the feeder. The pole from the first 3-way goes to the black to the load and the pilot hot. The feeder white and load white get pig-tailed to the pilot neutral and we're done. I guess you just have to figure out your box fill with the devices. Sounds like a deep box. Is that what you have in mind?
Joe

How about some 12/4 or 14/4?
http://appprod.mysouthwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet6

[This message has been edited by techie (edited 12-15-2005).]

It's definitely going to need a new box. This is old work. Next step is to decide whether to drill down from attic (longer run) or drill up from basement. Since I just finished reading the thread about guys drilling up through hardwood floors, I think I might fish down from the attic. It's not summer, so that's something.

Hey I like that 12/4 14/4. Especially since you don't have to buy a 3 mile long spool of it.

There's no law against flex.