This has been a very interesting read. Thanks to all for your knowledge and input.
However, for my car, I think I'm just going to leave it as is with (S/D??) OEM type UCA's.
My alignment guy was able to only get 3 degrees of castor with out jamming up the works. It does mean the car doesn't return to center quite a quickly as I'd like with spirited driving around bends, but it doesn't understeer either, so the work needed to get that extra degree or degree and a half may not be worth it. That said, if I were to decide to rebuild the front end again with performance UCA's etc. then that would be a different story.
I think at this point, all I'm going to get done is to increase the toe-in from 1/16th to 1/8th and see what difference that makes. Any thoughts on that?