Most necks are fitted with a dovetail join or bolted on. There's normally glue been the fret board and the top of the acoustic body. Some high end designs feature a floating fret board, but you don't see it very often.
Will post a photo, but the guitar was built with set neck then ply top added on, then the fretboard glued on.. Once I post the photos of the progress, you will think "Why is this guy Such a Cowboy???' This build is kind of a homage to home built, the concept of recycling, using crap laying around etc..Like a cigar box, crazy White Strips deal BUT based on alot of reading and research on Dobros and resonators and acoustic baffles and.....Basically a funky left of centre build. As I dont have any real tools I use what I can will follow up with my techniques.. Inspired by that great SBS doco Bush Mechanics.
Heres a photo of the underside of the fret board, it estends beyond the heel, I am removing the residual ply, so the new top will the glue to thew board. The new top will be 3mm Play.
Attachment 14133