Hi,
I was just given a couple of hardmodded xbox's by a family member. Looking at what to do with them as I haven't owned an xbox in 15 years. Stumbled across this site which looks like a great resource. It's only been a day but I have already opened one box up (build September 2002), removed the clock capacitor (which has already leaked and damaged the power button and eject trace), and replaced the thermal compund.
I'm here to learn so I will get back to it. Thanks to all the contributors.