Hi Weirdbits,

Thank you again for your advice.

You need to check how straight the neck is, does it have a bow or back-bow?
I have set my straight edge in the middle of the neck running from the 1st fret to 15th frets and 12th to 22nd frets and there appears to be no gaps at all.

Is that the way to do it?

Here are the
side-on shots (from bass and treble side) with the neck clamped in place and strings on showing the string height/action at the first few frets, 12th fret and end of the freboard
On bass side first:
Click image for larger version. 

Name:	Bass side 1st fret.jpg 
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ID:	9038
Click image for larger version. 

Name:	Bass side 12t fret.jpg 
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ID:	9039
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Name:	Bass side 22 fret.jpg 
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ID:	9040

next post for treble side...