If there is anymore stains or minor corrosion like your camshaft. Just use some green or burgundy colored scotch brite pads.
I say anywhere from 9.0- 9.25 compression ratio. Should give you better off boost response, quicker to get into boost, better drivability, better mileage.
Make sure your methanol injection (when you get it) is working if you are going to boost it high, anything over 10 PSI Who is going to open up your chambers on your cyl head?