Sweep1 and Sweep2 bodies were de-merged for a purpose. But when it comes to bodies to mirror, click on the body at any point is selecting entire body and Sweep2 is in the Body to Mirror box. How this can be understood?
You only have 1 body in your part:
Just did it without any problems. Bodies weren't demerged at first when I oppened the SLDPRT, double check that you have 2 solid bodies before the mirror.
File attached with the solution.
The merge result is set to on in sweep 2 making it one body.
Further merge solid is selected in mirror
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