Thanks Geof as usual
Here's what I did that seems to have helped...
First I changed go G71
I changed to 16tpi, because at 48tpi it was just too small and I was getting burrs like crazy. At 16tpi it is deep enough to be able to bite in and the thread looks pretty much perfect
I calculated the major and minor diameter in CAD knowing the teeth are 60 degrees and pitch of 1/16th". I came up with something of a diameter difference of 0.100 between major/minor. The threads were still sort of crappy until I switched to a 5-degree reflief away from the thread-in angle and just took 5-thou per pass. It is doing it in about 10 passes and I am sure I can speed it up, but at least it looks good for a starting point.
Now for the other side (mating part)