Nice earnings. Congrats. You can't delete the thread. Just delete the attachments by using the attachments option in the user control panel.
Thanks zainshah for sharing this information I'll do like this as you said.Thanks again for this information.
From all what others tell, it looks like a good job. One advice. Once you hit PR5+, sign up for the affiliate programs. That will likely give you some extra bucks for more link juice!