360 build questions.

OK, I was reading Larry Shepard's book "How to hot rod Mopar smallblock engines", and in there he was talking about when going with lighter pistons that the crank needs weight removed, or sumpin like that.

I know 360's are externally balanced. Has anyone else done this?
Externally or internally balanced, any significant change of piston/pin/rod weight calls for a crank re-balance, and removing material on the throws would be the normal course of action for lower piston and pin weight.