Howzit John. I can suggest a couple cheap, effective things.
Assuming you don’t have trap wires, Create two 16 inch loops of soft rope and put them on your side stays using a simple Prusik knot (a simple hitch that constricts when pulled but can easily slide up and down the wire when you want).
https://www.animatedknots.com/prusik-knot
You can also securely wrap 2” or wider Velcro straps around the bench seats just loose enough to get a hand under and to slide around in different spots.
Lastly, I use a kayak tie down strap looped between the wing posts to create a foot strap so I can lean out over the benches in a hiking position. If you are also holding the Prusik loop you’ll have a very secure position and will help drive the boat faster upwind. You can hook up a harness to it and everything is adjustable as well. For added comfort, pool noodles or pipe insulation can be used on the foot straps.
Cheers! RT
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Prindle 18
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