Learned this today while changing my GSR rear sway bar end links to Si units. The big washers that go on the bolt that connects the DC2 links to the LCAs can be used to keep the two nuts on the top part of the Si end links in place so you can tighten them. You can also find the same size washers at True Value or any hardware store. Since the Si rear sway bar does NOT use bushings but a flat mounting surface.

I am sure the more experienced people on here know this, so if you have not done this before, just a heads up...