im not sure anyone will say if it fits 100%.
EDIT: (haha... backed up by the first 2 posts

)
BUT... If you consider that a polo uses the same seats, and therefore same seat mountings, means the basic plan of the car is the same at the rear, ie... the bottom of the seat and back of the seat are the same as an
ibiza.
So the back of the seat rests on the front of the rear strut towers which is where the cage will mount...
IMO i think it will fit the same, but then thats just my opinion. The car is the same width and everything where the cage would mount.