Make mono audio clip "center-panned" without duplicating

I have imported some audio clips of narration that are mono. When put on a timeline, they play through the left channel only.
I found a trick here to go to Fairlight, use Clip Attributes, change Format to Stereo, and change both Source Channels to Embedded Channel 1.

This has worked fine before, but for a clip I have today, it results in the audio clip being duplicated on the timeline. Is there a way to do this without duplicating the clip. IE just change the clip to stereo?

Why not just create a mono track and drop the file onto it? Right click in the track header.