Again, thanks to everyone for all your input.

While in the shower this morning, I had a flash of brilliance as my
father's words came back to me: "avoid moving parts whenever possible
and shun automation!". While this little project hardly concerns
automation, and not much in the way of moving parts, the general gist
of his admonition was KISS.

So, along those lines, I started thinking simple (and crude). Here's
what I'm going to try. Take a 8'-2X4 and place it across the front of
the van roof, by the front roofrack crossbar. Now lash it into place
along the crossbar. Now I should have about 3.5' of 2X4 jutting out
past the side of the van. While I know I'm an idiot in terms of things
practical and mechanical, but I can't see a 2X4 not holding up this
kayak. What do you guys think?

Then, when I'm done, the 2X4 stays up on the rack next to the kayak.

Are there any flaws in this crude version of an extension bar?

Cheers,
Wilf
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