I did run into this problem! Tethered offers a great product. I was having horrible hip pinch. Once you sit in the tree for a few hunts or for practice you start to understand placement of the tether is important to help with hip pinch. I had to lower mine. I'm more of a leaner, so there are a couple things you can do here. If you like the weight savings of the amsteel ,first sit in your saddle and see if the length they have works for you. If not get some webbing and tie it to the saddle ( do some research and find a knot you like) Tie it on and shorten or lengthen it. You will feel the difference right away!
Once you determine the length you can get more Amsteel , watch g2 outdoors and greg goes over how to make a locked bremel and a bremmel stitch, I think he does that on his sit and drag video.