Make sure you get the correct oil, nothing else will work.
INTENSE-Racing.com: INTENSE Supercharger Oil (8oz)
The oil that can be used has been updated by GM, Mobil1 5W30 synthetic oil can be used.
You will want to get everything laid out, a small container to put the old oil in will be needed. Park car a flat level area. Remove the fill plug, the hole can be seen just above the spark plug wire.
Remove this plug with a Allen wrench.
Now you will need to suck the old oil out, this worked very well for me.
Once you have all the oil you can get to out, fill it back up with new oil. Put plug back in, and your done. VERY easy, and a quick job.