Air bag mounting?

[Envy]

How is everyone mounting the air bags on the rear? I just installed me CPP crossmember and trailing arms, but decided to be patient with mounting the bags. I started making assumptions and drilled to more holes in my mounting plate on the new trailing arm and then realize that was dumb so i called it quits till i got some answers.
Do you just run the one bolt into the center bottom of the bag? (similar to the single bolt on the factory spring) And if so, the bolt is only 3/8" so it has some play in the hole going through the trailing arm. So use a sleeve or just go with it?
Also, the original plate on the bottom of the frame that the top of the springs sits on, does that stay there even with the c-notch kit? Because the directions say to simply trim the outer edge but i didnt know if it would cause a gap between the c-notch bracket and frame.