Either I'm letting a rabid cat out of some bag, or I just haven't noticed until now what could have been in front of my face the whole time, but the feature which allows you to attach a file to the message is turned on.  SWEET!

I suppose that it available only in the sections that are designated "attachment" areas, because it is not an option for this post...  

What is this "UPLOADING FILES" deal anyhow ?  

Go to the "parts and accessories" section,
click on Lamar's post about 4 lug wheels,
reply to the posting (but you don't actually have to reply to it)
look all the way down to the bottom just above "post message" and "review message" buttons,
there is a place to put a file (such as a picture) "uploaded" straight from your hard drive.  
Much easier than having to have web space to store your pictures in order to post them on the message board.
That is all...