Pittsburg ? Russ Grimm on Monday. Ken Whisenhunt today. Does that mean the Pittsburgh Steelers might be ready to choose their next head coach by as soon as Wednesday? With the two Pittsburgh assistants being among the most-interviewed candidates for the four current NFL coaching vacancies, the Steelers are giving every sign they may not need to go outside their own staff to find Bill Cowher’s successor. Grimm, the Steelers’ offensive line coach for six seasons and their assistant head coach for three, interviewed Monday afternoon with owner Dan Rooney, president Art Rooney II and director of football operations Kevin Colbert. Whisenhunt, the Steelers’ offensive coordinator for three seasons and an assistant coach for six, will interview today.