New kitchen faucet messy installation...Help!

[Plum]

Hi,
I'm renting a home and landlord's plumber installed a smaller (cheaper) faucet. There's a horrible stain and mess left from the previous larger faucet that he didn't clean properly and sealed part of it over with silicone. How do I clean this up? I've attached photos (ignore reflection of camera).
Thank you!

 

[frodo]

if that is sillycone i am looking at.
acetone, and elbow grease

 

[SHEPLMBR]

Your landlord needs a new plumber.

 

[SHR]

That was no plumber. Handy hack cheap job...