Hi!
I can't help with some of the above - exceptSIJ.
However, there is not a pathway that is simple.
I have found Diane Lee's book "The Pelvic Girdle" very useful in organising my examination of LBP and Pelvic Girdle Pain. She has a summary page where all of her objective exam takes place and another page where patients get classified and general treatment principles are given.
Spend the money and get the book - it is well worth the money - I have earnt back more than 100 fold the amount that it has cost me...