Still down

It's been a while. Got 2 different saddle nuts in a mean time - wrong first and then correct one. Took weeks of waiting. Installed correct one last week, but issue isn't fixed completely. Saddle moves nicely when headstock is off, but as soon as I put headstock on, it starts to squeal. This suggests that alignment goes off under weight of headstock. Not sure what to do about it. Attempt to use it like that will most likely lead to damage of new saddle nut. Heard about some people using counter weight to balance headstock. Looking for solution at the moment. All milling and scratch building effectively remain stalled for now.