It has 3 ears like he said above. Same as the caliper end.
Look in the frame in next hole to see them.
If you replace them just put small flat screwdriver under each ear and open to break them. Ears are harder steel and doesn't bend much before breaking.
To save them small worm hose clamp to compress the ears. Is a pain but might work better then trying to compress then rotate each ear thru hole.
Clamp has to be all the way open to try and a big pain to install and try to close. Plus likely have clean the ears and inside frame there too.
Caliper end ears are easy to compress or break. Do that end first so have more slack for frame ends.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave