And yes, you need to cut down at least one of them. 1 1/2" sounds about right, I just did trial and error. I just cut them both at the same time. I use mine a fair bit when boondocking.
I used a compound mitre saw, made a square cut, then an angle cut to take of the top of the square cut.
2017 Escape 5.0 TA
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
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