These are the local attributes of an HQ (Core) item that CAN be edited. To view or edit simply click on the the product local attribute tab:
Then edit the fields as needed and click SAVE when finished:
For more information on how and when to use Item Exceptions, please refer to Item Level Exceptions for Tax and EBT Flags in the manual.
Case Pack settings under local attributes will trump HQ (core) settings and is only used for Suggested Ordering tool. Please refer to Suggested Replenishment in the manual for more information.