Use the "Post Reply" button rather than just typing in the "quick reply" pane. Just under the typing area on that window you'll find "Click here to Upload a Photo..." Click that, and you can upload a photo.
Make sure the image isn't too large (if it's larger than 2 MB on the disk you will need to use a graphics program of some kind to re-size it). When you click "Upload Now", the image file will be uploaded from your computer onto the BBS and a picture link will be inserted into the post.
Like this:
Can you describe where those first group of wires are? And what year is your 914?
--DD