So I love the product but didn't like the sag I was getting b/c of the way the Discovery's spare tire carrier just wouldn't let things get tight. Followed this thread, emailed with Dave about the pending production of a horizontal strap, but eventually decided that a fixed buckle solution would work ok.
Sourced some 2" bolt plates from here:
http://customtiedowns.com/hooks/bolt-plates/
Thenpicked up some 2" buckles (male/female x2) and triglides from REI.
I only used the existing webbing, after mocking up/measuring 3x/etc I took the plunge and cut the webbing on the trasharoo so that I could use up and down facing interfaces permanently attached to the tire carrier:
I chose the bolt both bolt plates in at the top b/c it is easier to reach down and grab both buckles from that angle. The duct tape has no purpose other than assuaging my OCD nature that can't stand excess straps since days of 782 gear gone by.
Obviously no weight/staged picture but the reality is the top straps physical length will limit it from sagging now. The bottom straps play less of a role, more to keep it held down and secure.
It's tight to manipulate back there but should do ok. Fairly well protected from elements/UV, and easy enough to replace down the road if need be. Since I'm not in an environment where I can leave it on day in/day out, the actual usage is subject to my ability to escape the Washington metro area. Will be interested to see how this turns out. For the most part I use it to store recovery gear like a kinetic rope and such.
r-
Ray