EE WAS INSTALLING A WHEEL SEAL ON THE LT. REAR DRIVE AXLE OF A BELLY DUMP. AS HE WAS HAMMERING ON THE WHEEL SEAL DRIVER, THE HAMMER STRUCK HIS LT. INDEX FINGER. THIS RESULTED IN A LACERATION THAT REQUIRED STITCHES TO CLOSE. EE WAS USING TOO SMALL OF A HAMMER AND MISSED THE SEAL DRIVING TOOL AND STRUCK HIS LT. INDEX FINGER.