Well assumming the Slackware installation tree is excessible by lilo on the PC, then you can just add it to the PC's lilo.conf and rerun lilo. Going by the info you provided above, this entry should work fine:
image = /home/slackware/slackware-10.1/slackware/kernels/bare.i/bzImage
root = /dev/ram0
label = Slack-Install
initrd = /home/slackware/slackware-10.1/slackware/isolinux/initrd.img
ramdisk = 6464
append = "SLACK_KERNEL=bare.i"
I tried it here and it works fine. If the installation tree is somewhere else that is inaccessible to lilo. Then you'd just need to copy the kernels/bare.i/bzImage & isolinux/initrd.img to the PC's boot partition so that lilo can find it, and adjust the above accordingly.
Hmm, I noticed in your 2nd post you mention grub, yet in your first post you said you wanted to edit lilo.conf to pull this off. So I'm confused as to which bootloader you have installed on the PC you're wanting to install Slackware too. Anyway, it would be similiar with grub, either one should work.