Key Blade Swap

[jayjay2cv]

Hi, on holiday at the moment in France, and my friend has had to have a new ignition barrel and key for his 07 plate Multispace, which means that his old Remote Key can no longer be used. He was given a spare blade with the new key to swap for the old one in the remote key, but wasn't told how to do it. Can anyone tell me how to get the old key blade out and the new one in please, as unlike my Mum's C3 remote key which looks similar, there is no screw through the case to release the blade? Thanks.