John you are right it’s how the 1962 medium case one I have works. The green dot style started in first and white dot in second.
The first ones in 58 did not have a vacuum module from what I’ve heard not sure on that. I was told that the one I have also could have the later 1-2-3 valve body installed but I wanted the green dot style.
There is no detent for park. There are 5 detents 1-2-3-N-R and a pressure above R held in by the column shift or floor shift.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

I am a bit confused with all this dots,when i put mine in 1 it stays in first gear,when i select 2 it shifts 1-2-3,when i select D it shifts 2-3. I have no way for the trick to shift first then second and stay in second gear.Here by a couple of pictures of the trans.

If you look at a stock 58-up Ford automatic indicator on the steering column the Second one below the neutral had a green dot at it. I believe this was to tell previous owners that this was the “drive” to use since the older Ford auto trans did not do this.. I do not know when Ford stopped this but for sure was not used with the C-4 or C-6.
The first D under N was a carryover from the earlier transmissions.
Since 6 spots were now needed on the column indicator of my 56 I had to lengthen the shift arm on the column and the shop doing the work shortened the arm on the transmission.
Your 1 is my L. The governor and vacuum modulator determine when it can stay in a gear along with what’s selected. I do not know how that works. I’ve never tried to hold mine in second gear.

56 Vic, B'Ville 200 MPH Club Member, So Cal.