I understand that but does the certi machine cut that extra material or is additional unshrouding necessary after using a certi machine?
I believe it is all about how it is set up- the answer being yes, maybe or no! The Certi machine makes cuts, not grinds so it is just another part ( step) of the operation, but might not be done if not specified ( sorry about the crappy explanation- its late!).The bottom line is it needs to be done if you go to 2.02, so see that your machinist knows that- the Chevy Power book says you need to go for a 2.34" total profile width. Also, David Vizard has an excellent book on working the -186 casting for performance.