James Riley at the forum of dpreview wrote:
"WARNING: DO THIS AT YOUR OWN RISK! I ASSUME NO RESPONSIBILITY.
This modification allows you to tilt and shift in the same direction, instead of at 90deg.
It is recommended that you send it back to Nikon to do this. When I got the lens, brand new, I had a project which needed the feature quick, so I just winged it.
1) You need a small phillips head screwdriver, and a small cutter.
2) With both lens and rear caps on, you can see 2 sets of screws (4 each) around the midsection of the lens. One set nearer to the front, the other the rear. The latter is what you want to tackle. To double check, the screw tops of that set should be facing the rear.
3) With the lens front side down on the table, gentle but firmly remove each of the 4 screws. Took me a while to get them to even move.
4) With that done, the lens breaks into two sections, and you will realize that the rear section is just a dummy case with the shifting mechanism and no glass, and a electronic ribbon cable coming from the front section to the rear of the rear section. The ribbon cable is actually longer, but has been "shortened" going back-and-fore and tied with a tape.
5) You will need to remove the tape to release the full length of the cable, in order to do the rotation. This is where the small cutter comes in. Very carefully, slowly, and gently, cut the tape, bit by bit. Do not twist or bend the cable, and don't even dream about accidentally cutting any part of it.
6) Now you can rotate the rear section 90deg from the original, there should be only one direction to make everything goes fine later, figure it out yourselves.
7) The trickest part is putting the rear and front sections back together WITHOUT grabbing parts of the ribbon between metals. You are going to have to play around with it to make sure of that. Once again, do this slow and carefully. Perhaps do the shifting and tilting to the full extent to make sure everything is fine.

Now put the 4 screws back in place.
Wowla!
I thought it was pretty "brave" to fool around with an expensive and NEW toy like that, but since then I have found that others have done it already, including Bjorn, as described on his site.
Good luck.
--
JR "
"Good luck" also from my side...
thom.