OK. Definitely is the blend door. I have removed the actuator, and found that it does indeed operate properly. I used a makeshift dental mirror (as recommended by this site:
http://home.earthlink.net/~kandc1/fo...nddoorfix.html), and found that my blend door is broken where the actuator's D-pin inserts into the blend doors' D-sleeve. So the actuator pin moves when the temp dial is turned, but the blend door does not move because it is "wallowed out" (pronounced "wallered out" by us Texans).
So, now I am weighing my repair options:
1. I could use the fix recommended in the link above, where I place a pin into the actuator's D-pin, which will push the blend door around, but may not work for long.
2. R&R the entire dash as recommended by Ford to get into the plenum to remove the blend door, then replace with a new one. A 6.5 hour fix for a $17 part. Sucks.
3. Cut a hole into the plenum, R&R the blend door, then repair the hole somehow. I have read somewhere that someone did this type of repair. As I remember, he used silicone RTV to repair the hole. This seems to be the way I am going to invesigate further.
So, M8s, I'll send more info on the developments as they occur. Now it's time for some watered-down US beer. :-)
Cheers from Texas. Thanks for everybody's input.
Brian