Banzai,
I just had the same problem. When I got my new cablle from the dealer, it looked identical. Once I got home and saw it next to the old one, it was a little shorter. Also, one of the plastic end pieces was slightly different. I shaved it a little with my knife and it fit ok.
Before you pull the old one out, duct tape the opposite end of the new one to it and use the old to pull the new one through. I pulled from the control end and with a little jiggling, it came through. I wasn't sure which way the heat control went after I had unhooked the old one, so I let the engine heat up and found out by pushing it both ways.
I couldn't get the non-control end to stay hooked to the duct, so ended up safety wiring it to the arm.
I don't know if the shorter cable is the cause, but I can't get the control cool enough now. I don't need too much heat, but do like cold AC when I want it, so I might have to adjust my cable under the glove box.
Hope this helps!