S4 with Ableton Live in deck D

Hey guys,

I have been searching all over and I couldn't quite find the answer I am looking for.

I want to run my S4 in Traktor, but have Ableton playing through deck 'D'

That is the "in short", but my ultimate goal is to have my midi fighter playing in Ableton on the on the drum rack (specifically the one offered yesterday for the MF contest). I want that to play through Deck D in Traktor so I can use EQ and filter.

I can get the setup by using my roommates mac (and mine) and a second sound card. Then obviously plug into the 'D' inputs on the S4 from the other sound card.

I can get them sync'd and have them both playing out of the S4 using only my computer, but it doesn't go through deck D.

I already have soundflower, but I am not sure how to set it up for what I am trying to do.

To recap - I have (1) macbook pro with Ableton Live 8 and Traktor Pro 2. I want Ableton (using Midi Fighter) to play through Traktor deck 'D', and out through my S4. I know how to sync the two programs, even though it isn't a big concern of mine. I just want Ableton to play over Traktor deck D.

Do I need Soundflower? Do I set Deck D to "live input"? one believe I literally just thought of, which seems a little "ghetto", is to have Ableton Out set to the built in sc on my mac, then have the headphone jack on the mac running into my deck D input on the S4.. but I believe that would sound like trash.

Hope someone can help, I believe this would be a nice setup for live gigs if it is reliable.