When working on removing the blend door motor make sure the temp control is in the centered position or it will loose its indexing.
This is a site I found a while ago with a cure for broke blend door. It has good info also. They say that you can open up the motor and recalibrate/reindex it if it has rotated out of spec they will include info on how to do it in the directions of the parts to fix the door.
http://www.heatertreater.net/Dodge%20Ram%2095-02.htm