Hey there!
I was installing Chameleon on an External drive and it Installed on my iMac Hard Drive. I don't want to restart. What can I do?

Grab a valid boot.efi and put it on /System/Library/CoreServices, make sure to chown 755 and chmod root:wheel.

Making those changes your iMac should be fine!

Where should I locate that? Also what about the "Boot file in the root of the HD?

Just grab the 10.5.7 update from apple.com and install using pacifist, and don't worry about that file.

Sorry to bother, but what package do I install?
I am also on 10.5.7
Thanks!

Boot using restore osx dvd and open disk utility;

Try a full format, deleting and erasing all hdd, on partitioning use GUID and create a partition;

Install osx as a usual.

I think this solve your problem.

Goodluck,