Here's the order:
Firewall firsts....EVERYTHING on the firewall, insulation, heater box, pedals, vents, etc...Then the dash as a COMPLETE ASSEMBLY.
Then wiring, dome light is most important not to forget.
You can now do the headliner and all the associated metal trim and sunvisors, mirror etc...Mark those holes by inserting the screws FIRST before the headliner goes in.
If the K frame is in, the steering column can go in.
Auto shifter can go in, then the carpet, console, seat belts
Interior panels and seats.