I was able to jailbreak and unlock a couple SIM-less iPhone 2Gs with the assistance of this link:
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I was able to jailbreak and unlock a couple SIM-less iPhone 2Gs with the assistance of this link. I know you stated you've tried Redsn0w, but perhaps the specific procedure and files mentioned in the link are different than what you've attempted?
I was able to jailbreak a couple SIM-less iPhone 2Gs with the assistance of this link:
http://www.ilikemyiphone.com/2010/02/10/...-activate-and-unlock-original-iphone-2g-3-1-3-firmware-using-redsn0w-windowsmac/