In order to remove old posts that you don't want is very easy. Find a post you want to remove and then in the bottom right corner you will find three icons.
First One - Folder with " " around it - I'm sure you know what this one is
Third One - Triangle with ! in the middle - this allows you to report a post that might violate the board rules / policies / manners
Second One - Folder with a pencil eraser (this is the one you want)
Click the middle icon and a box opens up like you are posting a reply. In this box is a link that allows you to delete the entire post or you can go in the text box and edit out what you don't like or add to what you replied with earlier.
Hope that helps and wasn't sure if you saw the reply from your earlier post that ended up disappearing.
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