Tether on the cosco vantage highback is very difficult to install. instructions are not clear, and it is not user friendly. if you have any helpful hints in how to easily shorten the tether for installation in cars please let me know. the exact model is 22560-fsm manufactured 6/15/07 why not use the tethers you install and pull to tighten like the cosco scenera 22120 fsm manufactured 6/18/07 these are much easier to install, very user friendly. please help make instructions and installation easier for parents. it is hard enough teaching them to use these car seats correctly every time, but even harder when things are manufactured in such a way that even an expert can't them figure out. (related vehicle information: model year=2004, make=buick, model=lesabre). *tr