Freelander 2 2008 Dash Heater Vent.

A minor thing l know, but it gets on my nerves so have paid £22 for the little silver heater dash vent slider. I imagined that it just pushed on, but it appears not. Do l have to remove the vent to fit it. Do l have to somehow remove the silver bit from the black fork thats behind it. I have done a search on the forum but cannot find any info on it, likewise nowt on the internet l can find. Any one fitted this little bugger, any help would be appreciated. At 70 l'm not the brightest tool in the box these days.

F2 is all modern wizardry to me. Wave a stick at it and say some pseudo latiny sounding words - from what I've seen with wizardry it'll either do what you want or all go up in smoke