hi there
its going to depend on just how bad it is, to remove the spoiler open the tailgate and remove the 4 bolts from inside the tailgate, close it over again and along the top edge where the water jet is you will find 2 torque screws, take them out then between the tilgate and the spioiler on both legs of the spoiler slide in something flat like an bank car and slide it up and down to loosen the doublesided tape it should come off after that, i had one and it was pretty bad, you need to keep in mine the corsas that am with a spoiler had a spcific tailgate and if you dont get one it involves moding a standard one which doesnt always work out to well
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