Yes, you can do this, but honestly, I'm not sure its worth the headache (I had to go through the same thing).
The problem is, its not only the kernel you install, but when you boot from the CD, the CD has a kernel it works from. So (if my memories of Red Hat serve me correctly) you not only have to put the RPM of the kernel in the correct directory (and on the correct CD), you have to change the boot CD's kernel and....yea, its a pain in the arse.
While this seems like a cop out (perhaps because it is, but then again, you have to pick your battles
), I would say either download the newest Fedora
(Red Hat, essentially) iso, or another Distro's newest iso, like Mandrake's
, or just buy a CD pack if your connection isn't fast enough (I would suggest Edmund's Enterprises
) for $10 or so (with shipping). Its a hell of a lot easier, and it'll save you some headache