Looks like an ideal project for @Andyjr1515 https://www.ebay.co.uk/itm/324583393290?hash=item4b92ad880a:g:OYsAAOSwPxNgf~ud Unfortunately, the truss rod nut has failed out of warranty, having either come unthreaded or broken, and just spins freely in its collar. The hex socket isn’t stripped and the nut is captive, so can’t be repaired or replaced by itself. Yamaha say they don’t supply replacement necks and that to replace the truss rod will need the fingerboard to be removed, a job th