you don't need an SST to remove the old oil seal, a large screwdriver will do to lever it out and you don't need an SST to fit the new one, just tap it in carefully with a hammer. Don't follow the FSM to torque the nut up, that's what has got Ryan into more work than he planned I think. Tighten the nut back up until the stake mark in the nut lines up with the stake slot in the pinion and stake it, job done.