You first have to get a Shipped ROM on there then run the unlocker. Take a look at
this link. You may be able to get one of these to flash. Just don't let the customizations run. When it gets to the screen that says touch here to setup, put the phone in bootloader and run one of the 2.4 unlockers. If you happen to go past that screnn just make sure you reset when the screen says customizations will run in 3 seconds and starts counting don. You have to be watching close and ready to reset. Post a question over there and see if the ones that have been through it can walk you through.
Wooohoo post number 700.
i just realized I didn't put the link in above. whoops. It is in now. That post has several of the stock pre-gps ROMs