Disconnect the drive shafts and tie them up.
Press the shaft flange with a pry bar.
Remove the seal with a puller.
Before mounting the shaft flange, insert the circlip so that both ends are immersed in the groove. This prevents the ring from deflecting to the sides. Press the flange of the output shaft by hand until the circlip snaps into place. Replace deformed rings.
Lubricate the seals with rear axle oil.
Drive in the seals with the bushing.