Those are a little unusual looking, I haven't come across any like that...
Looks like they have a welded in nut instead of a bolt,.. and some kind of dress cover held on with hose clamps...
... but,.. you can make them work... I have confidence in ya'...

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Tab mount, rail mount, and bolt mount, all had to be figured out at one time, too...
Now we got a nut mount...

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PS.. I think they may be CAT equipped,.. based on the heat shield cover...
...but, Harley Cat's are nothing more than a heater coil in front end of the muff.... so, it won't hurt anything...
...and you'll be cleaning up the world...

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Show us some pics of the finished install...

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