The CCC backside attack is here:

https://www.youtube.com/watch?v=dtviiOJ-2hI

It contains lots of info and technical details.

Another one:

https://www.youtube.com/watch?v=KVmpBPbGPsQ

This is what an actual ROM looks like:

https://docs.google.com/document/d/18IGx18NQY_Q1PJVZ-bHywao9...

As the last image shows, the ROM table values are extracted by graphics processing the photo.

It's also possible to dump the ROM by reading it byte by byte, but this depends on the architecture (not always possible) and is typically done for mask ROMs that contain data.