Editing The Text Version Of An Email
To edit the text only version of an email navigate to the Campaigns screen, then click the Options button next to the campaign you want to edit.
Then select Edit Email from the dropdown shown below
On the next screen shown below, click the grey Edit Email button
After the email editor loads, click on the drop down shown below and select Text
The text editor will now be displayed as shown below. Once you have entered the text for the text only version of the email, click on the Save button to save changes