If you are told they will do the install and warranty will not be voided, then they will back it. They are likely only giving warranty on the labor anyhow, they will not be giving you a warranty on the aftermarket parts. And it means that they are probably not the type of people to report your vehicle as they are instructed to do per vwoa.<This I know is true, and I know if they tell you what I wrote above, they are pretty much saying that they don't agree with the vwoa "mod turn in policy". I know this because all of my mods were done by my favorite vw shop...^-^