We use thin
dyneema too. I like the low friction/chafe of it and ease of splicing. Plus its
cheap. On one end of the splice for the lower lines I do an adjustable splice. Bury the end in a significant way through the center and then out with a long tail. The tail makes the loop adjustable so I can get the stackpack where I want it. To lock the splice I just do a couple of half hitches with the tail. This way I don't have to get the spliced lengths perfect the first time.