There are magnets available.
One option among many is
: Link:
https://www.homedepot.com/p/ACDelco-...9&gclsrc=3p.ds
Here is a picture of the Dimple in the pan for reference of the location. below is the tool you could use to do (Create that Dimple).
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Link:
https://www.harborfreight.com/25-pie...set-93539.html
You could use your favorite glue (In moderation) for a little bit of security that the magnet would not move// I don't think it will be needed if you put the dimple in the pan
You could buy a pan with and magnetic drain plug also.
Hope this helps
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