I did the swap on a 2006 325i, and it is the best mod I have ever done.
Here's what you will need to buy:
11617559523 Intake Manifold
11617559530 Vent Hose
11617579114 Adjustor Unit
11617560538 Adjustor Unit 2
11617547242 Gasket set
11617535849 x5 Screw 50x20
11617535850 x2 Screw 50x35
11617535851 x1 Screw 50x66
Figure just under $1k for parts.
The shop charged me $500 for install and another $500 for the Active Autowerkes Stage 3 manifold tune. It is an off the shelf tune, and it worked great, no tweaks necessary.
Hope this helps. Let me know if you have any questions.