Where to edit the TEXT email layout?

I have searched the forums, but everything seems to be about the HTML email layout, or the text email CONTENT.

What I need to do is modify the LAYOUT of the TEXT emails - not the content.

The text emails seem to be contained in a fixed-width div because the text does not span the width of the screen and this is causing issues with line breaks.

So...

Where can I edit the LAYOUT of the text emails? Thanks in advance!

The mails I am most concerned with are the Order Confirmation email, the Order Update email and the Registration Confirmation email.

Check this:

http://www.zen-cart.com/wiki/index.php/Customisation_-_E-mail_-_Format

The text emails aren't built from templates, they're built in the respective pages. You'll need to edit the code.

IPC1:

The text emails seem to be contained in a fixed-width div because the text does not span the width of the screen and this is causing issues with line breaks.
TEXT-only emails are just that ... text-only emails. There's no HTML in them, so there are no DIVs or SPANs in them.

TEXT-only emails do use the traditional 76-character line length so their content is compatible with as many mailservers as possible. Changing that is strongly discouraged else you run the risk of messages not getting delivered, with no evidence of non-delivery other than maybe a complaint that it wasn't received. Thus it is not a configurable setting.