How can I modify windbg is using ring0 on single pc?

welcome to the club of single pc windbagging
as far as i know i havent been yet able to achieve it
russ patch ??
you mean the utility by mark russinovich ???

if yes then it is called livekd and it is available for download for free
from thier site sysinternals.com

but even with livekd you can only find static structures of kernel in a single machine you cannot trace through kernel live
but it sure is a nice application and if you happen to have the book
windows internals something by solomon and russinovich then you can
actually find some good kernel info by using livekd
because it also fetches the symbols from microsoft symbol server for almost all the system drivers too

hope this is what you are looking for