.spl bootsplash

how do you create or edit the [resolution].spl files in the boot/loader/ area of the install CD? or otherwise go about making a custom bootsplash for an autoinstall? have been looking at whatever information I can find regarding gfxboot, syslinux/isolinux, and bootsplash but I am still having trouble getting anything to work...any how-tos you guys can point to would be great...or if you can nudge me in the right direction I don't mind putting a how-to together when I am done thanks for your time!