Jason,
The D model without the radar was originally designated the AH-64C, but since the radar could be added and taken off with a few hours of blood, sweat and the occasional tear by a ground crew, the powers that be decided to call them all D models. I have a few shots of D models without the "mushroom cap" seen in the pic above, but instead, there's just a "coolie hat" over the top of the rotor hub. The actual ratio of Radar (DWI) to non-radar (DWO) birds is about 1 in 3. Data links are pretty cool, though. Targetting info can be passed from the radar bird to non-radar birds almost instantaneously via datalink, so there really isn't any need for the additional 600lbs of avionics and radar equipment on every D bird. Of course, in my opinion, the radar simply says "SHOOT ME FIRST", but we won't get into that!
From what a few buddies in-country right now tell me, they're taking the radar off a lot of the birds to save on weight, since it really does no good fighting insurgents. The Longbow radar is great for targetting tanks and other vehicles, but against troops its just a big target.
The Twobobs sheet looks great! The birds that you can do on this sheet are from 1/3 AVN, 3rd ID during the initial campaign, and 1/227th AVN, 1st Cav Division as they are right now in Iraq (their second tour there). I'm profiling two birds from each of these units in my book, although different ones. I hope they decide to enlarge it for 32nd or 35th!
Hope my ramblings have helped a bit!