You will have to modify the install disk to do that, as the kernels used by it are included in it.
You will need a local mirror of Slackware 14. From now I will refer to the root of that mirror as /.
In /isolinux you'll fin a file named isolinux.cfg.
When you type:
huge.s root=/dev/sda7 rdinit= ro
the isolinux program looks in that file for a line with label=huge.s. The two indented lines after that one indicate where to find the kernel and what to append to the boot command line, to which it add what you typed after the label. In your case the kernel to use is /kernels/huge.s/bzImage (first line after "label huge.s") and appends "root=/dev/sda7 rdinit= ro" to the append command of the next line which becomes:
append initrd=initrd.img load_ramdisk=1 prompt_ramdisk=0 rw printk.time=0 SLACK_KERNEL=hugesmp.s root=/dev/sda7 rdinit= ro
So you could append three lines using the same template but with your own settings to /isolinux/isolinx.cfg. Of course put your kernel and initrd.img files at a location where you will refer to on the line beginning with 'kernel'.
Then make an ISO and a bootable disk as told in /isolinux/README.TXT
PS Actually you don't need to make a full install disk, only the /isolinux directory and the kernel + initd.img (that you could put directly in /isolinux) are needed , so no need for full local mirror.