I wanted to add a sliding seat for rowing to my SW Dory with sail option. The folks at CLC were skeptical, but with some helpful advice from Gary Pientedosi I made it work. The seat fastens to a deck plate on the existing thwart on top of the centerboard trunk, and to a removable support I added that rests on the trim around the edge of the cockpit, reinforced by a filet underneath. The center pin on each end of the support is a cleavis pin so that I can pin it from below, but that hasn't been necessary. Rather than the outrigger I raised the oarlock risers a bit and moved them about an inch aft. Alden bronze oarlocks work well with the new Dreher oars. Hobbyhorsing while underway was a concern, but does not seem to be an issue. When I want to sail I just pop out the seat, switch the oars, rig for sailing and I am off. There is a lot of technique invloved in rowing, especially with feathering the oars, but for this old guy just trying to stay in shape it works well and I am pleased.