Adhesive for rear Superb II Estate spoiler?

Hi guys!

Anyone here that used Polyurethane based adhesive to attach spoilers and wings to their cars with good result?

I received the SuperSkoda spoiler now, will soon have it back from paint but doesn't like the idea of making holes in the trunk lid to mount it so are now looking for alternatives and one that strikes me is using the same glue as being used for mounting windshields ... The surface area that will attach it to the lid is about two large hand palms so I believe it to be fully sufficient for the force that will be applied even at high speed. Not sure how well the spoiler fits apart from at the edges so I want something that fills up eventual empty space between the body and the spoiler itself which, to at least me, rules out any tape products.

Attached is a photo from the reseller, SuperSkoda.com ...

Ideas or suggestions? Every comment is welcome ...