Ive removed a saloon rear heated screen in the past, was a little tricky, but do-able, it can be done by removing all the interior plastic trim, and then cutting the black bonding with a very sharp strong blade. Once you have cut the bonding, carefully start to push the screen out all along the circumference of the screen clockwise, or counter-clockwise motion, using a pad, or some cloth to hold the screen a centimetre at a time, going all the way round until its free. You may need a second pair of hands to help you.