After a ridiculous amount of time spent dithering about this and that (all of it devoted to the rowing unit, actually), today I just said stop that and got on with it. I didn’t get on with much, but I got on with something. To wit: I installed a handle on the rowing unit, the better to hoist it in and out of the boat. And I installed a an aluminum bumper to stop the aft movement of the slider so that this bumper, rather than the plastic cushioning mechanism of the slides, would absorb any impact associated with a too vigorous push of the rowing unit (I aspire to such problems, but, in any event, they are obviated).

Next: the dovetails by which the unit will be clamped into the shell. I am trusting that things which seem mysterious and daunting now will seem more straightforward when at least some options are foreclosed. As in life, so in boat building, right?