if you get the bailey tank theres 2 ways to do it,both are right but 1 way doesnt allow the oil to return to the sump supposedly.if the engine is out then run the return to the sump,the other 1 to underneath the turbo into the block.there is a blank that needs removed,1 to the old kidney breather and the other to atmosphere.dont drilla hole in the rocker cover as supposedly a lot of oil comes back up this way and the only way for it to go is out the atmosphere pipe.i was told that by a tuner who experienced this on the rolling road.i have mine done the other way as thats what i was told and a lot of other people have done it this way.