It might be easier if i put down some styling options for consideration:
Option to do without CSS on a list basis (not global!)
-padding around images (left-right aligned) to 0px on/off
-box shadow/single css on a list basis ? 🙂 as soon as i add it to the custom css my recent posts widget(wpsp list) get a shadow too (global) :/
You would have to target each element within the inner post list to do that. Is the text the only other element you have, or do you have post meta etc..?