Installing new hard drive

I have a 2007 Mac Pro that came with a 250GB hard drive at the time. I installed BootCamp on the drive split 50/50 between Windows and OS X (sorry, I was stupid at the time). At some point I added a 750GB drive and moved OS X over to the larger drive. Since then, I added two more 750GB hard drives.

Tonight, I attempted to replace the original 250GB hard drive with a 2TB drive and discovered that when I moved OS X to the second drive several years ago, that the boot information did not go with it; so the original 250GB drive is actually the boot drive, while the second drive (the 750GB) has OS X. This leaves me unable to remove the original drive if I still want to boot the computer.

Is there an easy way to make the drive that contains OS X bootable so I can permanently replace the smaller drive? Unfortunately, reinstalling OS X is not really an option for me, as I would be forced to reinstall so much that I would lose a great deal of time.

Any advice would be appreciated.

Thanks

Michael

I'm not certain but I believe "rEFIt" can do that for you. Take a look at the documentation at their site and see if it will work for you. LINK I currently use it to dual boot between Snow Leopard and Win 7.

Other than that, I don't know of another way other than using your install DVD to create the boot sector and EFI partition.