Hey do this go to courtesy nissan parts online and look for dash assembly it has exploded view and you will have a picture of the view and screw locations. Hold on try this link.here is link for ac controls....http://www.courtesyparts.com/hardbody-truck-parts-d21-19865-1994/genuine-nissan-parts/body-electrical/272-control-unit/-c-3178_3179_3217_3235.html
here is link for dash full view look at part number 68520 dash ring hope this helps...........http://www.courtesyparts.com/hardbody-truck-parts-d21-19865-1994/genuine-nissan-parts/bodyfrontroof-floor/680-instrument-panel-pad-cluster-lid/-c-3178_3179_3298_3313.html