Simple 10.4.6
There is now a released package for updating a working 10.4.5 system to 10.4.6
This guide covers the upgrade from 10.4.5 to 10.4.6, click here to read a guide about installing 10.4.6 without 10.4.5
[edit] Simple 10.4.6 Guide
1. Install whatever update Apple puts out to incompletion (if it hangs at 50%), then force reboot.
2. Boot whatever OSX installation CD you like. Once the graphical install begins, go into Terminal from the apple menu bar. Run "/Applications/Utilities/Installer.app/Contents/MacOS/Installer".
3. Select in the window that appears, the Maxxus owned.pkg on his CD. Run it. EDIT from M u T T i: To run any app from Terminal /usr/bin/open must exist on your installation CD. If not, you have to start it from your original System. Example: typing /Volumes/NAME OF YOUR HARDDISK/usr/bin/open /System/Installation/Packages/Owned.pkg will run the said Packages.
4. Copy over a 10.4.5 kernel (mach_kernel) over the one put in /. Reboot. Works. You can overwrite the 10.4.5 decrypted files with 10.4.6 decrypted files later. (Or just copy over to a mass USB device all the files you need, mount the USB device in 10.4.5 fully installed, copy the files to the HD, do the unsuccessful upgrade and continue).
Remember that updating a working system is always at Apple's risk.