I was wondering if i could take a non-stock hdd, a 80gig seagate that i have lying around, and take the eeprom from my 10gig factory hdd (that came in my xbox) and then i could leave the 80 gig seagate in while playing live...is that possible or am i an idiot?

First of all wrong forum

And no you ain't gonna be able to switch your hdd.

The first time you logged on, you had a hdd. You ain't gonna be able to change that.