Sorry for the lack of details in my original post - here is the actual code that I am looking to find:
Content visible to verified customers only.
I did find code that looks like a match for this in the following template: adv_gallery_member_highlight_block
..but when I edit or (temporarily) delete it, it doesn't affect the code.
Let me know if I should pm you the URL for the site?
Thanks again for your help.