Ok back in a state of not so much intoxication, there is actully a few threads with guys that have done RBs with itb set ups one being I belive greg maybe with a 26/30 set up with itbs and the other an rb20 race 32.
Can it be done, yer sure. You need a custom inlet manifold to mount them to and obviously 6 itbs, a decent aftermarket ecu and general fabrication skills help if your doing it yourself as alot of the stuff will need to be made custom for your car.
Also going to rephrase what I said in the earlier post (also as Simon has pointed out), NA performance isn't a waste of time, so good results are achievable but on RB motors making any kind of mind boggling power is practically unattainable no matter how much cash you throw at them, for example gregs only made ~170rwkw, which is all well and good until you consider the fact that the motor and all the fab work has cost a small fortune and your still going to get chopped left right and centre.
Can it be done, hell yer it can... Is it worth it, I don't believe so, it does look/sound cool though and it's something different