just replaced the heater and evaporator core and man am i glad i had the diy instructions from this forum. i must have missed something though... when i turned everything on afterwards i get air comin through the defroster and floor but i cant get any air to blow out of the front vents. this happen to anyone else? is it likely the switch or something i missed on the backside when i had the dash out?

 

Sounds like the cable that controls the damper could have been disconnected from the dash controls. Remove the bezel and pull the HVAC control cluster and inspect the assy to see if the cable is connected.