If they are 7.5" wide they should be okay 51 offset is stock offset with a GTI and so the wheel will be 3mm further in to the arch.
If I go into pedantic mode then you'll have a slightly narrower footprint, but no biggy.
If the wheels are 8" wide, then the offset will pull 9mm in towards the arch (check for damper clearance!!) and poke an extra 3mm out from stock wheels.
HTH.
