Set aside a week.
See if you can get a new one from Holden still.
Dash out.
You’ll be working in the engine bay as well. I had to remove the wiper cowl to get access in there. Plan to replace the clips. Do a search on the forum. I posted a photo of all the clip types and part numbers for the wiper cowl.
Brake booster will be removed from the master cylinder. Master cylinder stays. Booster will come out with the pedal plate.
Steering column can stay in. Just lay it on the floor.
Get a new texta
Buy lots of zip lock bags. Big and small. Bag bigger parts so they don’t get scratched.
Get a few plastic crates. Put all the bags in the crates organised into groups. Eg. Engine bay. Interior trim and say dash fixings. It will speed up putting it all right again. Of course everything is labeled in bags. Screws, parts. The lot. So quick and easy. All your photos to follow the reinstall.
You’ll need to get the insulation off the fire wall around the booster. I don’t fully recall if I had to remove the centre section. Coolant can leak from the heater hoses into the insulation. Check those. You’ll want to be checking the brake master for leaks. That will be easy to do once the booster is unbolted.
I also had to remove the top of the motor (easy job) to reach into the area a lot easier.
If you pay someone, you’d easily be up for thousands in labour.