This is a photo taken under a bright light of the first part of the yoke s/n . The new s/n is CME1xxx, the old s/n is TRD08xx. The model number is 325. In most light the old numbers are not easily seen or photographed.
I've decided I'll email the photo to S&W customer service and see what they have to say.

I've decided I'll email the photo to S&W customer service and see what they have to say.