[s-cars] ECU Modification

[Twobro12 at aol.com]

Question:  I was looking at the pictures of ECU removal on URS4.com (getting worried about my ECU upgrade considering all this talk about the end of the MTM ECU!)  and I was confused as to the precise location of the ecu underneath the carpet.  It states that the ECU runs next to the transmission tunnel, which i presumed to mean it would be forward and to the LEFT of the passenger seat (facing foreword), yet the directions tell to pry off door sill.  What is the reason for this and how should i approach the install?  Sorry for any problems, I'm still learning about these beauties.

THANKS!!
Mike 94 s4 with no mods, little knowledge, and lots to learn!