You can easily hotswap it out on an error 16, I just repaired one myself.
Simply follow the hotswap instructions and either leave the power hooked up to the HD from the Xbox and let it sit at it's error screen, or hook both power and IDE up from your PC and turn the Xbox off once the drive is unlocked. It doesn't matter either way.
As for damaging anything, I highly doubt it. I've heard talk of there being different voltages between hardware. BULLSHIT, they are standard PC drives fed off the exact same voltage. If you want to be safe though, use some alligator clips and ground the metal shielding in the Xbox to your PC chassis.
You aren't going to be swapping molex connectors while EITHER system is running, so theres nothing to worry about as for a power spike into the hard drive.
I've actually hotswap modded 8 different Xboxes this way. Theres also no reason to unhook the DVD drive in the Xbox either.
As for which softmod I used, I used the latest NDure package, but I would assume others work just fine too.
Also, with regards to re-locking the drive........when you hotswap you're simply catching the drive as soon as it is unlocked by the Xbox bios and swapping it out to your PC. I believe the Xbox locks it up again after checking it. Once you've used XboxHDM to copy your stuff over, and you shut down your PC, the drive is back to being in a locked state again, you don't need to leave the Xbox on as the key is a matching set to begin with. The only way it would remain in an unlocked state is if you disabled the security entirely. DO NOT DO THIS!
You have no need for a chip unless you've got yourself a locked harddrive that doesn't match up with the motherboard, or you've disabled the lock entirely. Otherwise once the drive has no power, it simply returns to a locked state.
Hope that helped.
This post has been edited by IJTF_Cinder: Jan 8 2006, 08:13 AM