Acoustic Guitar Construction

Actually I do have a taper fixture to run through one of our drum sanders so I could taper the bottom before or after the slots are cut. But yes you'll have to make sure there is enough depth in the slots so the frets seat all the way down.

For what it is worth, I glue the fretboard to the neck first, do very fine adjustments as part of attaching the neck and fingerboard to the body, then do more fine adjustments after attachment (like leave more relief under the bass strings than the treble) which assume a flat fingerboard top as the starting point. Then install frets. Never had a problem with pressure from the fret tangs messing anything up but I understand how this could be a worry.

Thank you gentlemen for the very helpful insights.