My wife and I hang under a Noah's 12 using the Dbl hooks/spreader bar. I typically pitch my tarp pretty high anyway, but there is room to lower it some in our case. We also use the 36" bar, I hadn't thought about shortening it but might give that a try.
It does help to have a wider tree on the head end if at all possible.
Keep working at it, you'll get it figured out!
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