Hey thats great man. I just got the Begi in and rocking.... I think I'll do something similar. My thought was a similar piece in the duct over the engine to push air to the back of the vent, so it funnels down over the manifold and downpipe area.
Id leave all the existing ducting and fab an aluminum sheet to block off the front 3/4 of the vent over the block. Does this make sense? I guess it would also allow the intake and battery venting to remain in place as well. With the Begi being a litle smaller, Im not quite as worried about the radiator as the bigger TurboXS guys would be.