In step 1) where the link is provided clicking it produces the following result:

" /var/tmp/CQwUs6dR.exe.part could not be saved.
because and unknown error occurred.

Try saving to a different location. "

Anyone have a workaround?

Attempting to use the autoinstaller to install 2.6.28 ends at:
"Installing nitdroid-kernel-2.6.28-06_finall_armel.deb ...failure. bailing out"

EDIT: Found the problem. I installed Power Kernel and Multiboot myself before runnning the NITDroid installer and apparently NITDroid installer likes to handle these dependancies itself.
I used Settings>Clear Device and then flashed my N900 to remove the Power Kernel then downloaded and ran the installer again. 2.6.8 stopped at Formating ext3 so I upgraded to installer 2.7 and worked like a charm (but installed popov 0.0.8).
Only problem now is finding any software whcih works with this version from the Android Marketplace (Adobe Flash Player 11 does not and many of the games don't make it through install, killing themselves in that process) beyond Open Office Reader.