Name that wire??

Hi,
I have a blue and a gray wire going into a connector plug which has slightly angled terminals. The plug is located under and inside the drivers side kickpanel. Can't find it in my 72 diagram? Is it something to do with the seat belt light or buzzer that is attached to the two floor mounted front seat belt holders? Can I just close thbis up without hooking these or do they belong to something I am not aware of???