Where are Mail.app's configuration settings stored?

I am trying to write documentation for Mail.app, but whenever I delete ~/Library/Mail and go to re-enter my settings, I notice that some things are kept, such as the SMTP Server List, whether or not the incoming or outgoing server uses SSL, etc. Where is this information stored? I am trying to get screenshots of each step when I am adding an account, the screen with the checkbox for "Use SSL" when you're configuring the incoming server is skipped during the account setup. I just want to clear all of Mail's settings and start from scratch. I've already deleted com.apple.mail.plist from ~/Library/Preferences but this doesn't seem to be doing the trick.

Edit: I did some more searching and found /Library/Mail/MailAccounts.plist. However, it doesn't include the SMTP Server List.

That's not going to do it. Some settings seem to be retained after clicking the minus sign, as I've explained.