I've tried searching for this, but no luck.

I'm trying to insert a weld connector on the end of a sheet metal part.  I'm getting the error "Edge weld connector should belong to faces of surface bodies or sheet metal bodies."

I can select any other sheet metal face in the model, except any faces on this part.

This part is a mirrored sheet metal part.

Do the weld elements not recognize mirrored parts, or am I doing something else wrong?