Permanently delete a guide via the deleted items options menu:
Open the Content Outliner.
Scroll down and select Deleted Items.
Click the deleted item options ellipsis and select Permanently Delete.
Click Permanently Delete.
Permanently delete a guide via the bulk actions button:
Open the Content Outliner.
Scroll down and select Deleted Items.
Select the guide you wish to delete by clicking the check box to the left of the guide title.
Click the caret on the bulk actions button and select Permanently Delete.
Click Permanently Delete.
