Subheading for Custom Post Type

I was searching for this answer but didn’t find anything.
The posts about this issue where closed, so I opened this threat to share what I did.
I am a noob at this so I have no idea what (if any) problems I may have caused by doing what I did. All I know is for now it seems to work.
What I did is mess around with line 86 to 89.
You can do a couple of things. If you want to ONLY show subheadings on a specific custom post type just change the ‘post’ on line 88 to your custom post type name.
If you want to ADD subheadings to a custom post type add the following code between 90 and 91:

$this->meta_box('page');
			if (isset($this->options['posts'])) {
				$this->meta_box('INSERT CUSTOM POST NAME');
			}

This was my noobish solution without any idea of why it works.

Would it be easy/possible for the plugin maker to add in the admin page a way to “add custom post type name” and the plugin auto create this code with the name you put in the admin page?