Bought the cobra jet intake manifold kit from more. All is good, I'm not a mechanic, but I'm mechanically inclined. Second time pulling out a intake manifold and replacing it. So far this seemed to be easier than the 01 4.6 I did. But this kit does not come with evaperative emission canister purge valve bracket (evap)m-9444-m50. Is there someone that's done this intake swap? What is a evap and what does it do, and is it necessary for this install?