Courtesy of NACHO...
to remove the complete dash frame assembly ( pad, frame, wiring and cluster )you need:
-Unplug all wiring attached to body or extra harnesses: Blower resistance plugs, rear harness on drivers kick panel, dome roof harness, both door jam switches, orange undercarpet wire on passenge kick panel if is floor shiter and power windows harness if is equiped. Of course also unplug harnesses from bulkhead and remove bulkhead/fuse box assembly screws from firewall. 74 has a grommet to feed the A/C blower, so unplug blower on engine bay and remove grommet from firewall.
Also, brake pedal wires and clips from steering column/brakes pedal brackets, hazzard flasher. Emergency pedal brake plug on driver side kick area. Cruise control wires... rear speaker and rear deffog from drivers kick panel area if equipped.
-Unplug harnesses from column and let drop the column ( 2 or 3 7/16" nuts/screws )
-Unplug speedo wire form cluster.
-Remove valve heater wire from cluster control and vacuum lines plug.
-Antena wire. This one need to be completelly removed from dash frame
-remove dash speaker panel... 4 1/4" hex screws and 3 phillips
-4 3/8" hex screw attached to top of cowl area with fasteners ( below windshield ).
-last step, ONLY LOOSE ( not remove ) 2 bolts, 1 on each side on kick panels. These are the last two bolts that supports the Dash assembly weight from car.
After that, just let drop the dash frame and remove from car.
2 guys is better to take care.