If you want to post the dyno make sure it is in jpg or gif format and click the attachment button below. Locate them on your system and upload. If they are too large it will tell you. It will take a bit of time to upload if you are on dialup.
You can try to upload it to the gallery and then put the image in the thread with [.img.]http://gallery.fordforums.com/linktoimage.extension[./img.]
OF course take out the .'s around the img tags and use the link to the image in the gallery instead of what I typed. :)