Can I use the cylinder head of 03-04 for 05-06?

You're starting a few threads related to your engine so you may want to consider an engine build thread to keep everything concise

You're not breaking the rules per se, but, if you start a thread like "Kimchi Rider's Engine Rebuild" you can update the thread as you add more pics and go through the teardown and you can bump the thread if you want to ask questions on which parts to use or other advice instead of multiple threads each with a bit of information.