maybe i can help u out.
it is not necessary to make these changes in your old kernel.
I think you just want to run your newly compiled kernel, to use ATM.
So, edit lilo.conf:
You should find your old kernel there (something like this: image='your old kernel's location here')
Now, just copy-paste those 4 lines, BUT replace that image location to where you copied your new kernel (bzImage).
After these type at prompt:lilo
When you reboot, hit <SHIFT>.
Now you can choose, what kernel you want to use.
Hope this helps.Best regards Wolve