I do believe someone here has reported shaving enough to take all the flat area out of the chamber.....that would be in the .100" range, + or -. The remaining chamber size would be in the low 50's of cc's.
To get to 60cc with a 2.02 valved 360 head... it usually only takes about .060-.080 , some cases a hair less. The heads can be anywhere from 69-74 cc as cast with part of that due to valve size and the amount of chamber they take up... just like tulip 2.02 int port measure 155cc while 1.88 versions measure 160cc..
