Cutting the overlap down to the minimum 8" might be a good idea for future installers, mine rattled like crazy until I shortened the inside section of the bars. A ton of chatter bumps on these dirt roads doesn't help
Attach bag to frame mount and make a template with the two holes for the bottom of the airlift bags. Transfer the template from bottom of bag to block when they make contact, then drill the tang with a right angle drill.