I have a 98' F150

I recently had to change the light bulbs on my instrument panel,when I put it back together while running the air condition I notice no mater where I set the dial the air would not come out of the front panels. I tried taking most of the dashboard apart to find the cable that controls the panel door but no luck.
Can any one help me locate the problem or the device I need to be looking for??
Thanks for any and all support in this matter
La.Handymama
PS. I just read the page for bender door help I'm not sure if that applies to my situation. The A/C works but it only blows thru the top vents by the windshield

 

If all you did was change a couple lights in the dash I dont see why the blend door would be a problem as it is in the black box that houses the heater core and condenser. I would think that a part of the dash was installed properly. I would take it all back apart and do some investigating.
P.S. Also, the blend door controls the temp. of air coming out of the vents, not whether or not the air comes out.

 

I was trying to change my post to be more specific.
Ihave a 98'F150 While changing the lights I heard a sound like a spring coming off I looked then but didn't see anything. Later after putting everything back together and driving my trucking turned on the A/C and notice the air would only come from the vent by the windshield. Last weekend I took apart most of my whole interior trying to locate what I thougt might be a loose cable or spring found the vacuum motor that controls the air flow direction Pulled down on it and it opened the panel vents W/the engine running it slowy releases itself back to close of the panel vents. My truck is still torn apart it would like some helpful info before I decide to put it back together regardless