2004 A3 8p 3.2 3dr with Bose sound, need stereo fascia help

[Panscrank]

Hello there.

1st post.

I did check through the search but couldn't find a solution.

I have just purchased a 2004 A3 3.2 3dr with the Bose sound system.

I bough this aftermarket 7" Alpine unit https://www.amazon.co.uk/dp/B09RSFQ1QC?ref=ppx_yo2ov_dt_b_fed_asin_title

And this fascia adapter: https://www.ebay.co.uk/itm/281902518707?fits=Car+Make%3AAudi|Model%3AA3&_skw=CT24AU15+Audi+A3+8P+2003-12+Car+Stereo+Radio+Double+Din+Black+Fascia+Facia+Panel&itmmeta=01J82PXG16VC0RB9NN39CCB2SM&hash=item41a2b311b3:g:2qEAAOSwzZFd75r9&itmprp=enc%3AAQAJAAABMHoV3kP08IDx%2BKZ9MfhVJKnZ%2FGaDWuDC0q0gZe267IGTc9xIDhTP%2B9zk8PcjSpqBFT4sy0%2B4TANww4b%2Bd%2BnXMe%2Bg1IcMhVWK2x3d%2Fn2QzGk%2FebQQwSuMLt1IYYTJdSu0wnN2uYFsxI2i8pk2aQHFJrPCkpF2k9m46IkD5%2BU90g73yDTeKtqJZ3KUDoC9hvNLQ%2FQnid%2FewMDRHK%2F1%2BbaHwuE2aBg9sGGVNVqQb60vicphHMfAms9QHSwkGpCJCEBevBJ0ipYE3uWeFQsX68mORXB0EICXo9ofi5BIoH%2FpfkvqAwuzXIPWsc2W2XMhcuRoLNX2%2FxUI35UnhsFBjljlhiFjyJSYn9fzcewEDmkrRdxh1kqQCMgTB6JVr1kqXh652HeAXWb9tiNCH8SnID6%2FLP8%3D|tkp%3ABFBM2oD21sBk

 

The fascia fits into the space beautifully but this stereo I have bought is way too small to sit snugly in there.

Do I need to purchase a double din cage, as there wasn't one with the unit. And if so, is there a specific one I need?

Do I need a different fascia?

Looked around everywhere but all i can see is ones like the one I bought already.

 

Any help greatly appreciated.

Edited September 18 by Panscrank

[Panscrank]

Can anyone help? Surely there are others who have installed an aftermarket 7" stereo to an A3 and have solved this issue previously?