In other news, your plate turned up today.
It is, as I feared, the wrong size. And, the centre groove/holes aren't 1/4" UNC.
Nevermind, I'll find some use for it, or sell it if I can't.
Cheers, for the thought.
I managed to rig up a solution today -- I went to Specialty Fasteners yesterday and bought a bunch of 1/4" x 2" bolts and nuts and replaced the ones that were in the two clamshells. Works nicely.
H