GTI or Golf R exhaust fit facelift A3?

[Geraldb5s4]

Hey guys, I've been wanting to put dual/quad exhaust on my 09 audi a3. Will GTI or Golf R exhaust fit if lengthened a little or is it totally different underneath? Or other suggestions on a exhaust setup that will fit? Thanks!

[Dad A3]

I have the APR down pipe and Miltek exhaust on 2012 FWD DSG.
Both are interchangeable with GTI, only difference is length of exhaust tips.
Never seen it done with quad tips, I'm sure somebody on here has done it and provide details.