For as far as I understood aluthman this was required on every FSI block. But like I said I looked at it briefly. My FSI is still in crawling steps to becoming a stage 3, which is when I plan on stripping down to a bare block to build from ground up and I look at this mod. So to answer also at Justin question, no I have not performed this myself.
All my info is based on reading online, hence why: take it with a grain of salt lol
Put this question up on vendorzine or any of the mkv or a3/a4 forums and see what it fishes… Sometimes you do get lucky to hear someone out there that actually know what they are talking about - they are probably from here lmao.
With all that said, hence the technical involvement this would take and the budget involved to get a reputable shop that would know how to do this, I would second though this mod (that’s what I did for me stage 3 project)
Is this block gonna be used for a racing purpose, maybe I would invest in this. For me, spirited drivers/weekend warriors I didn’t see the investment worth the return.
My 2c