If it's anything like the sedan, it would be MUCH easier to drop the subframe. I bent my own SLS supply line on a euro sedan, and it was a major PITA. I did manage to bend it up and over all that crap in the back, though -- didn't have to drop the subframe. If I had it to do over again, I'd have just cut out the bad section of line and flared the ends, then dropped in a section of new line. My bad section was in the straight length right under the pass seat area; the rest looked good. Good luck!

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1992 300D 2.5T
1980 Euro 300D (sadly, sold)
1998 Jetta TDI, 132K "Rudy"
1974 Triumph TR6
1999 Saab 9-5 wagon (wife's)