Do you have a center brace, how did you get it by there if you did?
I do have a center brace. Like I mentioned I cut the sheet 5/8ths short on all sides so it just fit inside the upper lip and the megaflows actully sit a tiny bit beneath the center brace. so I slid it under the center brace and back ontop of the second megaflow "flat". I figured this out after ten minutes of trying to jam it in other ways, LOL.

