Updating Kickstart NFS Install tree with new RPMs

[A Cline]

Hey all:

How can I update the RPMs in an NFS install tree with current RPMs that 
I have downloaded using up2date?  I want the latest RPMs to install via 
kickstart when I do the install.  I'm also interested in adding a couple 
of custom RPMs to the installation process as well.  The information 
I've found on the web thus far has been sketchy.

Thanks for any info

A Cline