[Peepaw]

Originally Posted by Frank Ford

Here's a trio of articles I posted when I first started FRETS.COM around 22 years ago - they may give you some guidance:

How to Check Nut Action

A Closer Look at Nuts

Setting Nut Action

Those were early days of digital photography (for me, at least), so please excuse the comparatively low-res images. . .

Thanks a ton for those articles Frank, they answered my questions.

The 3/16 number was the main thing I was looking for. I watched numerous videos and read numerous articles on filing slots. None of them gave any number for how wide that area should be.
I figured it needed to be as narrow as possible without being so narrow as to wear down way too quickly.

Looking at your pictures I take it that the ramped part of the nut should slope or fall away from the string.
Am I correct in that assumption?