the picture is 500x200 and the text adds another 15 pixels to the bottom of it. reize the pic down to 185 pixels tall, remove the link, or make the image clickable to take you to that link.
also, it looks like you hit the enter key a few times in the sig box to create room between the post and the sig, you're gonna have to take those out.
Dave is going to be taking out all html coding from the forums, so you're gonna have to use the forum code. it would be something to the effect of
[ URL=http://members.cardomain.com/mattlb2200][ IMG]http://registry.gmenthusiast.com/images/mattlb0619/redcavisig.jpg[/IMG][/URL]
without the space before URL and IMG. try and get it to work using Preview, and if it works, then you're set.