I am going this way pretty soon too. I am going with the fitting similiar to Quadzilla's. Should be airtight.

I saw this for an IDI engine. Don't know if it really matters because of the volume of air flow in DI?
You can make a dispersment tube aid by taking an old piece of copper tubing a few inches long, squashing one end and drilling some holes in it about 3/4 or so of tubing length. This goes into your intake hose.