Hi there hope i can be of assistance.
Is your micra fitted with rear brake drums or discs?
Thanks for the reply,
Ok, the rear wheel bearings are in the brake drums.
The bearing are an inteferance fit into the drums so these will need to be pressed in and out using a hydraulic press.
If your worried about cost, you could remove the drums yourself, and take these to a workshop for them to install the new bearings in the drums.