UPDATE!

Okay. I got Tiger installed using Target Disk Mode. The machine boots ... but no video. >

I can hear the Tiger intro music so I know the machine is booting. The LCD lights up and is gray but there is no video at all. I noticed that while I was running it in Target Disk Mode that there was no Firewire logo but the drive showed up on the PowerMac I was using to build the machine so I went along with it.

I have re-opened the bottom of the machine and verified that the LCD connector is indeed inserted where it should be. I have reset the PMMU.

I don't have a mini-VGA connector to try an external monitor. What else should I try? Any suggestions?