Have you tried holding Command+Option+X+O to boot it from the ROM instead, and remove the extension from there? (or you could use the boot disks from the Apple website)

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I tried that also, just a moment ago. Doesn't work.

I was hoping it wouldn't come to reinstalling the OS, since I like to look around and see what's on the drives before I wipe them.

I know there is a key combo that works... I wish I could remember it.