I believe my "66" Tele's nut, intonation problems on lower frets, what to do?

[58Bassman]

No, this has been a slow gradual thing, once I learned about intonating guitars, for I work on my guitars. Once I learned how to intonate a guitar relating to the bridge, the nut, and crowning, is my next stop. on this learning expedition. I've ordered a nut, I haope with my research and study, I'll be able to det that up correctly, than. on to crowning. I'll get there.
Thanks
Rick

I didn't see any mention of string gauge- I switched to light strings on the offset Tele I recently bought because I had stopped playing for awhile and need to build my callouses again- I have problems with low frets but to add some neurosis to the equation, I check intonation at the 7th and 19th frets, too- if the harmonics and fretted notes agree at all three positions, it shows that the fret locations are right, but if it gradually goes sharp or flat as you go up and down the neck, it shows that the action is off, one way or the other. If I use the harmonics at the 5th fret to check the tuning between adjacent strings, I can get that right, but fretted notes are off and if I get the open tuning right on a tuner, the fretted notes are wrong.

I'm in contact with Fender because of a couple of other issues, so I'm waiting to do anything about the intonation.