As the Original Poster of this thread, it has been over 6 months since I first posted about 'screeching notes'. I'm happy to conclude I've solved the problems. No more unmusical sounds while bowing! To sum up, it appears simple and logical now. Working to this end was anything but simple, due to my own long held beliefs. An open mind works wonders when problem solving. Here are my solutions, for my bass and technique:
Arco Specific Strings
In my case I went with Bel Cantos. I put on a number of strings on in the last 6 months, stark spiros, dominants, and combinations of them. I understood Joseph Guastafeste, ex CSO Principle, used spiro starks on his Busan and Gasparo da Salo his whole career. Hey, if he did it, and my bass with starks will loosen your gold fillings...
Well, Ken Smith opened my mind up to arco strings for bowing, and helped to get me away from the jazz growl (that I love) on this bass if I want to bow. David Potts was correct, once again, about arco strings for bowing.
Carlsson Rosin
Carlsson rosin is great now with the Bel Cantos. Nymans sure looks like the same rosin. Pops worked when I was using spiro starks, but is just too sticky now. Plus it leaves a mess to clean off, and somehow adds it's own 'rosin sound' to bowing. Yep, David is spot on again.
Practise Most Days
How simple. I found when I got too busy with gigs and missed a day or three of bowing, my bowing chops flew out the window. I mark on a calendar my bowing time. Works for me.
So thanks to the good folks at TB for advice, Ken Smith and a few others, I have worked past this bowing problem. I have a lot of sheet music I had been holding off playing, but now is very playable. The bass I have the Bel Cantos on is used for bowing only now, I have a jazz bass with spiros for gigs.
Thanks Guys