Here's a picture of the Apollo 6 optics during its post-recovery inspection; In this photo, you can see the ablative panel and optics which were removed from the spacecraft prior to it being put on display.

Click image for a 1211x1365 pixel version of this image in a new window.
From p. 5.4-29 (p. 159 in the PDF) of Apollo 6 Mission Report (alternate link)
Extraction and cleanup by heroicrelics.

The scan quality of the Mission Report is rather poor, and I can't find S-68-3676 anywhere else on the Internet. If you know where I can obtain a better picture, please contact me.

Here's a picture of the optics taken on the recovery ship:

A full-size crop from S68-27041