WARNING: This page is about a different car, the 2010 Audi Q7, 2009 Audi Q7, 2008 Audi Q7, and 2007 Audi Q7. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Identifying Ignition Coil With Power Output Stage
Courtesy of AUDI OF AMERICA, LLC
Installation is in reverse order of removal, note the following:
-- Place ignition coils in respective spark plug shaft so the straight connector sides fit with each other -arrows-.