Well here is the evening update. Overall not to bad, just time consuming. All I have left is to put the main dash in and front panels.
Big thanks to Jaccox23 for helpful info.
While I am not doing a complete write up, I will post the highlights and things that make this easier. 1st, there is a great YouTune video on removing the dash. Covers everything. To this I will add that you will need to remove the corner front trim to get the dash off. Also, the only cable from the HVAC that needs to come off is the center vent cable. Get that off the vent and after removing all the bolts the dash can be lifted off.
Now to the real fun. Removing the while Heater core box. After trying to be very gentle failed many attempts, had to put grunt force. This required destroying the old copper tubing from the old core. I removed the rubber connectors than broke off the copper. This will make it easier in pulling the box off. Keep in mind u have to disconnect the 2 heater hoses in the engine bay. If possible saw off the 2 copper tubes going through the firewall. Will make it much easier in getting everything out as these make it hard to pull out The rubber boot will come out and will be reused for the new cooper lines as they go through the fire wall.
The white box has 2 large bolts on top and 2 on the bottom. Believe 12mm. Jaccox23 gave a great tip in completely removing the center frame where the radio/HVAC controls sit otherwise the box will not come out. Major tip here. Loosen the 2 top bolts holding the condenser box and 1 on the bottom. (pic 3 has the 2 top bolts) Do not completely take it off, but get it plenty lose. This is the key in getting the heater box out but more importantly back in with the heater core in the box. Just to be clear here. No connections from the ac condenser were broken, so no release/evac will be needed. You are just moving it some to get the heater box in/out. Going back in is the real ***** as it goes in right end first then pushing in to get the copper tubes back through the firewall. With this new core design, I tried putting the tubes through the firewall 1st than connecting to the core as the new clamps work much better. The issue here is you cannot secure the tubes on the back of the heater box once in. Pulling the ac condenser box out was enough to snap it in.
Time for few beer and to reflect on the old heater core's demise. (Hope I can get all this **** back together without extra parts left over...)
Now is a great time to take some pics of the old heater box so see what parts on top will need to be moved. The controls on the left do not need to be touched as that part with the top flappers will be connected to the new black heater box. The box is held together with clips. In the new heater core package you also get new clips. Take your time as the flappers are old and can break. You also need to remove the 2 large flappers from the old box that will be trashed. I attached a pic of the new black box and what remains from the old unit. Take your time, use your pics and move everything over. Before installing, pull the cables to ensure all flappers work as needed.
In the morning I will hook up the batter and start the Monty to ensure the core connections are leak free, then install the dash back. I will take picks of the center vents and how they sit in there.
Vid link on removing dash
https://www.youtube.com/watch?v=VyDP1QUncHg