Just use whatever fits in there...
Use some kind of oil to help with the cutting.
You can use WD-40, Liquid Wrench, or even regular engine oil if that's all you have laying around.
For rotors?
Use Chem-Dip.
I noticed our local Walmart started to carry this.
Do NOT get this on your skin, so be very careful how you handle this stuff.
For housings, I like to use a water-based cleaner like Zep purple industrial cleaner - at Home Depot.
I also like the Oil Eater cleaner that Costco used to carry, but this stuff isn't too easy to find nowadays.
I find the other cleaners like Simple Green, Super Clean, and Purple Power to be TOO WEAK.
-Ted