[my80chevette]

I have a Comet that I installed replacement recovery software on, UltraJack Recovery, and then installed a custom rom. I then decided to return the factory rom to the system only to discover that it was corrupted. Now I have found the original T-mobile factory rom but when I go to put it back on I get a "unsigned or failed verification error when I try to put it on. From what I have found looking up this error I need to install Clockworkmod Recovery but the one on Google market isn't compatible with the Ideos or Comet. I have the 5.0.2.8 version of Clockwork but it is a cd image type file and supposedly you need fastboot or adb to install it and I havent messed with those yet. If anyone can help me out I would really appreciate it.