Not plymouth, I mean the actual boot splash that gives you the options of trying out ubuntu, installing ubuntu, checking the disc for defects, etc.
It appears that everything concerning this is in the "isolinux"folder on the ISO. I found some info here: Splash screen before Ubiquity install
But when I follow his commands to create a new bootlogo cpio archive, the boot fails.
I figured out that changing txt.cfg changes the text on the boot menu without needing a new bootlogo, which is great, but I'm having issues changing the .pcx images and gfxboot.cfg. I'd also like to turn off how ubuntu automatically chooses to open the graphical "try or install" window if you don't make a choice in 5 seconds.
Thanks a million to whoever reads this.