Hi, I have just bought my first car, a mk6 zetec s(2006) and I would like to swap out the radio in it to something like a pioneer radio, this would mean that I am able to use my subwoofer and amp I have purchased. As the fiestas have a larger unit in the radio stock how would i be able to fit the radio in, does anyone know of anywhere to buy an adapter to fill the gap it would leave or know of anywhere to get a larger radio that will fit and know the dimensions that isn't too much more than the radio I am already looking at (£50).

Thanks all in advance.

Does the pioneer stereo come with a facia plate to cover the sides? Is it single or double din? Theres a guy on YouTube called JayMono who had an ST and in one of his vids he bought a android double din stereo for his car. Was £110 and looks good with the features it has. 

On my mk6 fiesta zetec s I fitted a underseat sub (with built in amp) and wired it to the speaker output with the standard stereo. 

£50 is cheap for a car radio. Are you sure it has enough power/features to feed the amp and sub?

The fascia plates are cheap enough on Ebay. You can get either a single din (doesnt look very good as youll have a more basic radio than what you have now) or go double din and get a touchscreen.