Rule #1 - Be Patient - Rule #2 - Don't ask when, if you don't contribute - Rule #3 - You have coding skills - LinuxMCE's small brother is available: http://www.agocontrol.com
If I were in your shoes, I would just run the regular detection process, let it create everything, and move the stuff over to the HDD, and let it boot from the HDD instead of PXE. Might even work without a lot of manual configuration.