Thanks for the clarification on the rounded edges. And yes, I know a full boat tail would be better, but I need it to be functional for daily contracting and family use. Not sure I could get a full boat tail to manage that.
As to the hitch carrier acting like a crude boat tail, I agree that is likely a possibility. I did another trip recently without the hitch carrier, and only got 30.5 MPG, or there abouts, and with similar speeds. I did go into the mountains though, rather than toward the coast, so that could have had something to do with it. It does give me an idea that maybe I should play around with a hard sided hitch carrier box thats more streamlined for when I do need more storage space. It might achieve a boat tail add on function and added space. If I do, I'll keep you all posted.
I also added a few more pictures so that the structure is more evident. I also added gas struts today so the lid lifts and doesn't require a prop stick.
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