I'm finally back into the garage today and after some cleanup I was able to build a jig for fret slotting. Then I was able to slot a fretboard in just a couple minutes and it's perfect.
Building patterns for different scale lengths should also only take 5-10 minutes.
This is amazing. Next step will be to taper the fretboard and then put in the frets.
Before you know it I'll get this tenor finished up, it's been a long haul.