Permissions

SO..I am currently following this tutorial on installing SassC and LibSass on Ubuntu:
http://crocodillon.com/blog/how-to-install-sassc-and-libsass-on-ubuntu

I am at the final step:
The final step is to make sure the sassc command is in your PATH by creating a symbolic link in /usr/local/bin/.

cd /usr/local/bin/
ln -s ../lib/sassc/bin/sassc sassc

and when I use command root@:/usr/local/bin# ln -s ../lib/sassc/bin/sassc sassc

I get error: ln: failed to create symbolic link ‘sassc’: File exists

Because I am assuming I've tried this command earlier when I did not follow the instructions right and created a corrupt file.  Therefore I need to delete.  But because the folder came in permissions blocked I haven't had a clue on how to delete this sassc file already in the folder.