how to get the old heater core out?

Hello,
If you have the dash out then you should see the black HVAC box left attached to the firewall. The box should be removed by removing those bolts from the firewall. Hopefully you have evacuated the A/C system because the evaporator will need to be disconnected for removal. I will attach a picture of the heater core panel on the box to look for.

William

I need to know where the bolts on the firewall are. Do you have any other diagrams that show a more complete breakdown of everything needed to replace the heater core?

Here is a video to help you do the AC work, you will need to remove the heater box plenum so start by draining the engine coolant.

https://www.youtube.com/watch?v=4EqdrBVb0sY

You will need to remove the dashboard and the heater box is held in by screws inside and outside at the firewall. This is a big job but if you take your time you should be able to get it done. If you have problems, please upload a short video or images so I can help you. Check out the images (below). Let us know how it goes