Macintosh HD>var>folders>jw>jwHG3BlB2RWHxU+BYmsoq++++TI>-Caches->com.apple.Safari>
The "jw" & "jwHG3BlB2RWHxU+BYmsoq++++TI" bit are specific to my Mac - it will be a different set of letters on yours. However, just go into var>folders and locate the one which has an unlocked -Caches- folder, then the com.apple.Safari folder. It's a bit of a rummage, but worth it if you're limited in disk space.
Applemacster