Hi Firespawn,
You should be able to set up an update query using the "ch** (" as your selection criteria in the field that it appears. On the update line put whatever you want to replace the existing data to, for each field you want updated.
Then set up a macro which executes this query (the action is Openquery and enter the query's name in the action arguments section). Additionally, if you don't want to be warned by Access prior to it performing the update, enter the action SetWarnings with action arguments of Warning On to No, prior to the OpenQuery action in your macro.
Hope this helps.