Hi All

Sorry, attachment didn't work.

What I'm thinking of is a U shape aluminium block, the vertical arms of the U run up the fore/aft edges of the inside of the beam, the bottom of the U supports the head of a cap bolt, a smaller hole is drilled into the top surface of the beam to allow access with a hex key.

I hope that is clear, if not, any pictures or diagrams you may have would be appreciated.

Regards