There is lots of discussion on the forum pertaining to set-neck builds, locating the bridge etc.

One thing you'll commonly read is focusing on the overall scale length not the nut to 12th fret x 2.

There is also a handy PDF Building Guide: http://pitbullguitars.com/wp-content...s%20Manual.pdf

The guide also describes how to temporarily mount the TOM bridge posts/bridge specifically for finding the correct scale length.

At the risk of sounding like a smart-arse, if all else fails, read the instructions