Here's the jig attached to two of the ribs.  The twisting motion of the jig when you tighten it down locks the jig into place - no need to clamp or screw it in place.  Before turning the bolt to apply pressure, you can tilt the jig in/out to match the angle of the strip you want to apply pressure to

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Here's the opposite view of it.  The construction materials are:  (1) approx. 16" long piece of 2x2, (1) 1/4"x4" coarse thread bolt, (3) pieces of beaded strip, approx 1 1/2" long.  I cut two 3/4" wide slots 12" apart on center (the spacing of my ribs), about 3/4" deep.  I then drilled a 3/16" hole in the center and tapped it to 1/4-NC.  Next, I glued the three beaded strip pieces together, and drilled a 1/4" hole in the center of the middle strip, on the flat back side.

Bottom View

You could easily make five or six of these for very cheap, and securely hold your strips in place at several locations at once.  For the middle two ribs, which are closer than the rest on my design (not sure if this is universal), you will need a different jig with the notches spaced 11" apart on center.  Also, if I was concerned about my beaded block slipping off the bolt, I could notch the end of the bolt around the perimeter, about 1/4" from the end.  I would then drill 2 holes in the block and put two spring pins in (one on each side of the bolt, engaging the slot), to keep it captive.