Exhaust manifold replacement

Here is a guide that will help with step by step instructions on doing this type of repair:

https://www.2carpros.com/articles/exhaust-system-removal

Below is the process from the manual that will help with the detail needed as well to complete this.

However, if you broke the studs then you need to continue with the others and remove the manifold and then hope there is enough stud left that you can extract it. If not, you are going to have to try and drill it out otherwise you are going to need to remove the head and take it to a machine shop.

Please keep us posted on what happens. Thanks