RE: temp, do you keep an eye on it or...?
The Castor oil syndrome is a myth. If you want to gum up the insides of your engine and subsequently clog the bearings then use Castor oil. As recommended Powermaster 15% is suitable without the addition of any extra oil. Break in the engine with the fuel you intend to use for flying. Apply some logic. why would anybody break in an engine with one fuel then use a different fuel for flying. Doing that starts the whole break-in process over again. Different fuel, different rpm, different heat range.
Read some of the European engine sites. They laugh at the use of Castor.
Ed S