Because I build and paddle kayaks without deployable skegs or rudders, I always test paddle my kayak builds prior to installing the coaming so I can trim the CG location to assure the kayak will be wind neutral (in a cross wind). Adjusting the seat location is the easiest way to trim the CG location which influences if the kayak will weathercock (turn into the wind) or leecock (turn downwind). And seat location then determines the cockpit and coaming location. I install the coaming last so the hull and deck are totally glassed and epoxied, and I also epoxy seal the cut edge of the undersized cockpit cutout, so all wood is waterproofed. I take the coamingless kayak to the local bay in a brisk wind and test paddle crosswind. I move back in the cockpit while paddling until the kayak quits weathercocking and note my back location in relation to the deck. Knowing my back location I then can locate the rear of the coaming. I like my fist (5 inches) to fit between my back and the finished coaming. This process assures that I will be able to paddle my finished kayak (without ballast or cargo) in a crosswind with minimal crosswind correction.

The only hitch to this is method is the rear bulkhead must be at or behind the aft edge of the final cockpit opening so the installed bulkhead may limit moving the coaming back. It is best if the aft bulkhead falls right at the edge of the final cockpit cutout to expedite draining water, when performing a rescue (re-entry). I install the rear bulkhead after installing the coaming. And I install adjustable foot braces at the front bulkhead.

If you install a deployable skeg you want the kayak to weathercock when the skeg is up and leecock when the skeg is down.

Rudders should be the most efficient if the kayak is wind neutral when the rudder is down.