They are easy enough to adjust, most are a threaded rod on the end of the cable, with a nut for adjustment. On mine they are marked as to where they go. Not sure if there is some kind of procedure to follow or not, I tightened it some, put in slide, ...
I put one on after debating about it for a year, I like it, helps keep it a little bit cooler inside. Does tend to pool water after a rain,But that's easy enough taken care of. It was easy enough to install with some help,took about a hour for a 12 f...