Yeah definitely look the same.
Online part catalogues show that the middle box for the BWA engined GTI and FR are very similar with different suffixes...
Middle silencer:
GTI - 1K0 253 209 AQ
FR - 1K0 253 209 AH
Backbox:
GTI - 1K6 253 609 BG
FR - 5P0 253 609 H
Obviously the parts catalogues show the same diagrams for both cars.
And...
Comparing the two with online images they both look similar.
Both very similar from the back, and roughly an equal distance from edge of number plate.
Suppose the only real way to find out is to measure them...