This page from the Rover manual shows how to remove the radio.
You will have a fascia that holds the radio instead of the Harmony but the principal is more or less the same.
Remove the cover under "eyebrow" then the two screws, then pull the fascia forward and unplug the radio.
You will not need the removal tools shown in no.4 just tilting the facia and radio forward will allow you to remove it.
Then you can remove the radio from the fascia pushing in two clips on each side of the radio..
This shows the radio and fascia.
Dave T