Mac Pro 8-Core CRISIS!

I am pulling my hair out and would love any advice or help I can get! This is kinda long, so please bear with me.

I recently bought an ipod touch (32G) and began the installation process on my Mac Pro (8 core – 1st release). Upon hooking up the ipod, the OS (Tiger) told me that I needed to update to 10.4.11 (as well as itunes), since I was currently running 10.4.9. I proceeded to download the update, and the installation began once it had downloaded. Here is where the problems began. What I failed to notice was that I had less than 300 MB of space left on my hard drive. The installation got to a point where it couldn’t go any further when I realized what the problem was. I tried adding things to the trash to free up space, however, when I tried to dump the trash, it crashed Finder and restarted it, never allowing it to empty the trash. Hence, I was halfway through the installation, and my 8-Core was STUCK. After several hours of it doing NOTHING, I had to force quit the installation, and reboot the system. Needless to say, the Mac was pissed. I repeatedly go the kernal panic, without fail. (That made me PANIC too but I tried to remain calm as I had a lot of work on the main drive that was irreplaceable!) I ordered up a new SATA drive, and upon arrival, I hooked up my older Powerbook G4 to the Mac Pro via firewire and booted up the Mac Pro so that the Powerbook recognized all of the drives. Thankfully I still had all the data there, so I made a copy using Carbon Copy Clone to an external USB bare drive, in case something else happened. After the cloning was completed, I ejected the clone drive, and using disk utility, I erased the OS drive in the Mac Pro, got my Tiger install disc, and rebooted the Mac Pro to do a fresh install. But the Mac Pro just flashed the file with a question mark on the screen. The SuperDrive was spinning away, but it never engages the install process. So I put the Mac Pro back into firewire mode to see if the disc was there. This time I hooked it up to a G4 tower via firewire, and it recognized the original OS drive (now bare), the two additional drives in the Mac Pro, as well as the Tiger install disc. So I though, maybe I can try installing it from my G4 via firewire. NOPE! Not an option! So I ejected everything and tried to boot the Mac Pro to the install disc again, both by just starting it up and also by holding down the C key to try to engage the install disc, but NO LUCK. I am so frustrated and cannot figure out a solution! Does anyone have any ideas of what I could try? I have some pretty time sensitive work that needs to get done, and the deadlines are looming quick. I would hate to think I have 8-cores of JUNK! HELP!!!!!! PLEASE!!!!!!!