Another interesting observation. I did watch a couple of videos and neither said anything about bending the calipers. The Park tool video (which are normally great) did not even mention how to make any adjustment for noise/chatter.
I did attempt a stop from a faster speed and got some squeal but still a huge improvement over the howl it used to make. Also, for reasons I don't know why, it would make noise every forth or fifth brake pull. This happened over and over again like it would squeal on multiples of five or so! Maddening.

After some experimentation I've got them adjusted so it is mostly silent stopping at various speeds while pulling the brake successive times.
Just as advised, the front half of the pad must engage the rim first while there is a 1-2 mm gap between the rear half of the pad and the rim.
Any more taper, the noise comes back. Full pad even with the rim as originally set up, horrendous noise.
So, thanks to your guys' help, this went from frustration to one of the most satisfying repairs I've done. Now I brake with a grin.