you want teh E-Type shimano mechs, you just unbolt the bb bracket.
There are a few parts that come with the frames so make sure you have it. There should be bar/bracket about 2" wide with 3 holes. There are spacers that go in 2 of the holes to offset the bracket up or down. You then bolt the derailleur to that bracket.
I bought some random XT e-type and it worked fine (I did have all the Spesh provided parts though). The only thing I had to change was the cable fastener to a regular nut since the head has a thinner profile and clears the frame.