WallyKilla - Not sure if you typed that in "jest," or if I missed some other banter between the two of you?? If not, disregard. But please remember to keep all personal conflicts to PM or e-mail with your fellow board members...
In any event, reading the 03/04 Cobra FAQ "sticky" is a great starting point for information regarding the differences between 03 and 04 snakes.
A couple of quick differences between the 03/04 from the top of my head are paint schemes and the 10th Anniversary model. 10th Anns were only '03 models and for '04 only, did Ford offer the unique "Mystichrome" paint job.
The old official SVT website did a good job of offering info regarding each SVT product and differences among their vehicles (it offered PDF documents for download). I've found that the Yellow Mustang Registry has a good "cobra" production number breakdown page (if paint scheme is of interest to you):
If you are looking for mechanical differences between the two model years, you'll want to dig through the Terminator FAQ for further info though and try other resources. I can't remember any glaring mechanical differences between the two model years, but there may be small differences out there I'm not personally aware of.
You cannot just own a Terminator without doing some research. I do not remember giving you any advice before but I will give you some more now. You should, at a minimum, read the Terminator FAQ, your owner's manual, and Iron Fist Lead Foot. This will help you understand what you have.
Anyways, I went ahead and got you the link to the exact information you are asking for: Terminator FAQs