I don't like down time or wasting money, so I opted to jump on seasonal specials while my car is still running like a champ on the E85 Freektune / BNR S3. The benefit here is I've now got a core worth a substantial amount of money, and if all goes well, a weekend swap and no time spent driving...
After doing a few of these, I decided to make a text guide that filled in some of the blanks that I'd seen in some of the more visual guides. This thread will be much better with pictures of course, and now there are more professional installation guides available from vendors such as...