Really nice build! If you have not already decided on the intake I would consider these plenum chambers. They are really nice and I used it on my turbo conversion. Inexpensive and really good quality. http://www.mwsteel.eu/en/tietoa_virittamisesta.php
The idea behind the design is that you will get an even flow on all the runners. Google Audi imsa plenum chambers or Audi grp B plenum. Below is a simulation proving the engineers where doing it right..