Bring a tape measure to do some testing. Find two trees that have only 13' clear between them. You'll have to use marlin spikes in the straps and set them right next to the tree. Then hook your whoopies over the spike and shorten them almost all the way (but leave enough of a loop to get a couple of fingers into). Finally adjust the whoopies to get a 30* angle (FROM HORIZONTAL). Then post a picture for us.