On my 2011 Outback I made a reticulating arm out of 3/4" (or 1" I don't remember) hollow aluminum bar stock (you can find it at Home Depot or almost anywhere, even Amazon). I added a gear track up near my front hatch just in front of the steering anchor points. A good tip is that toilet flange bolts are perfect for using in tracks. I even found matching plastic knobs at Home Depot.
The nice thing is that it is easily removable and adjustable (I used it on 2 different kayaks and a small jonboat). The downside is that having it hang off of one side is that you create drag and the kayak wants to pull in that direction. I used it like this for many years so it was well above acceptable to me.
If you are interested I can get it out and take some pictures.
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Fish tremble when they hear my name
A ship in harbor is safe -- but that is not what ships are built for.
--John A. Shedd, Salt from My Attic, 1928