Michael suggests:
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You want the most support you can get. This is especially true with a
plastic hull. You can either cut into a deep crosspiece (like a 2x6)
or make a saddle that bolts to the crosspiece. The latter will be more
flexible in allowing for lots of different configurations.
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See what you think about this: I cut deep into the 2x6 crosspiece
(rectangular cut) and then create a sling using a fairly wide webbing
strap (perhaps 1.5" wide to correspond to the 1.5" cross-section of the
2x6).

I don't know if this qualifies as a "saddle", but it would seem to
conform ideally to the hull curvature and also transfer the mass of the
kayak, via straps, to the crosspiece. The issue here, I guess, is
ensuring that the straps can be securely mounted to the crosspiece
(grommets etc, eh?).

Or am I getting too complicated (and perhaps flimsy) here?

Michael, you have an uncanny ability to "send me back to the drawing
board". Thanks, I appreciate the input.

Cheers,
Wilf
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