Copyright 2017 "Musical Instrument Repairs WA (MIRWA)"             All Rights reserved    E-Mail: service@mirwa.com.au
Since the neck cannot be removed, I suspect its been epoxied in place, the option we have for doing a neck reset, is to machine the old fretboard away at an angle and fit a new board on top.

We start by removing all frets.
We fit and strap the guitar into place
Using a piece of paper, we calibrate the nut end of the fretboard and the top of the bridge to be the same height.
I use adjustment nuts on my cradle to raise and lower each corner.
Adjusting the bridge to be at the same height as the nut end of fretboard.
Once the guitar is squared and levelled, we add a small scissor jack under the headstock for support.
Using a 1inch (25.4mm) wide router bit.
We machine the old fretboard away, note the old remnants of the fretboard are now wedge shaped
Before I start, I notice that the fretboard is a different colour at the neck join, this could be indicative of the guitar having had a top change and / or, the neck was cutoff, clearly this instrument has had other repairs.
Normal process to remove a neck is to drill two steam holes at the 15th fret, this was done, but the neck still would not release.

Attached link for neck removal standard process
I have a leather support cradle for guitars when using my overhead router.
Using the cnc, we machine out a new fretboard
"How To" Neck Reset Acoustic Vers 2
Necks stretch over many many years of use, the wood itself stretches and also the glue joint that holds the neck on can also creep.

This guitar is over 50 yrs old, the neck angle is far from ideal, we need to remove the neck, set the new angle and refit.

Sometimes the neck wont be able to be removed, it could be becuase it has whats called a spanish heel or the neck could be epoxied in place such as those fitted to ovations.

Time to repair approx 6 hrs.