I just spent the afternoon doing this little project as our first PCA club concours is next weekend. Changed my brake pads out as well, as they were a bit too worn for me for a DE in a few weeks.
This is one of those things that if you keep them clean all the time, it's not that big of a deal (love those 5 spoke CaymanS wheels!), as I always do a full wheel clean, wipe off the calipers, and wipe down the wheel wells every time I wash. But, to go 10/10s, you need to use something on the wheel well plastic, and get in and around everything you can't get to with the wheels on, etc.
Using a detailing spray when you wipe down / dry your wheels and brake calipers every time pays off big dividends........
And, it is certainly one of the keys to having a car that people look at and can't quite figure out why it looks so clean.
Regards!
Phil, I did my engine a couple of weeks ago, and it came out great (another 3 hour project). Thanks for the suggestions!!!