Is the pinon gear is already out of the truck and are you working on removing the race from the pinion gear or the race in the housing. If its in the pinion gear I usually cut them off carefully with a grinder making sure not to score the shaft as this will cause problems later. if its the housing race you need to come at it from the inside of the differential with a long punch. You should be able to catch the edges of the race from behind looking through the differential from the gear side. If your hesitant about grinding the pinion race of you can use the big red wrench to heat it and tap it off when hot. Hope this helps.