I'd like to create a customized Debian or Ubuntu LiveCD to boot a hosted diskless server. I'd only be adding VirtualBox. However, I'd like use about 4GB RAM (out of 8GB total) as ramdisk, and (if possible) install the entire OS in ramdisk (for performance). The remaining 4GB RAM would be plenty for VMs that I want to run. I've been reading about Remastersys and Ubuntu Customization Kit. Would either of them do what I want?