This may come a little late, but i have had trouble with the same thing, only not a severe. When i would shift the pointer would be in a certain position, and the actual cable another. I checked under the dash and discovered several loose screws which atach the cable to the shifter linkage. after tightening them up, i had no more problems. The shifter linkage would lock into say, the neutral position, and since the cable wasent firmly attached to the linkage, the tranny would not move from drive.
Hope this helps!!
