So I just pulled mine off the other day (need to modify them to work with my passenger back rest).
From outside in (bag to fender)
The metal bracket attach to the Exhaust Supports, all the way at the rear of the bike.
Hope that this is what you are looking for and that it helps.
2015 - Magnum X1
2008 - Kawasaki MeanStreak SE 1600
2011 - Vegas 8-Ball
2009 - GSXR 600
2008 - Yamaha Warrior 1700