Through the glove box opening you'll see tandem actuators for the recirc flaps. Stick your hand in to the left and up and you'll feel the defrost actuator. You have to remove the ACC control panel to get to the center vent and footwell actuators. I've never seen the diverter actuator but I believe it's inboard of the accelerator pedal.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD