I have recently done a Time machine back up of my MB Pro 15" then wiped my hard drive trying to clean it up so I could install Windows 7 with Boot Camp. I had my original Install Disk which I forgot was Tiger, Having used one of my brothers company licenses to upgrade to Leopard but that disk is now with him in another country. So now I can not restore from my Time Machine backup. I have a Leopard Install disk for a Macbook Pro 13" which I also own. Is it possible to use this disk to re-install Leopard on my 15"?