Technical Radio Removal

[Gwilllo]

Hi folks, I'm trying to remove the head unit to replace one aftermarket one for a new blaupunkt unit. I've slid the keys in to remove the old one but it only moves a couple of mil and then feels like it's trying to pull the whole dash off rather than just the radio coming out. Any tips please?

 

[LeftyGreg]

You might have pushed the keys in too far, they should click a few mm before fully pushed in