A hammer is often both the right and the wrong tool for the job. It's the technique that makes the difference.
In Tony's hands, the hammer was the right tool for installing the new pinion seal. The technique was to use light blows and to work the seal into position a little at a time by alternating the hammer blows around the seal's edge.
After spraying a coat of grey Cast Blast paint onto the drive flange, Tony then slid the flange onto the pinion splines. Next, he zipped the pinion nut (which had been prepped with red Loctite) back onto the pinion with the impact gun.
The driveshaft was then re-attached. The final step was to top off the gear oil and thread the plug back in.
Now for some more on-and-off-road abuse!