windows 2000 setup from external drive

I've searched every bit of MS documentation and the Internet generally and can't find a solution to this little problem.

I have a small workgroup of three computers all running Windows 2000. They became infected by viruses (Blaster and others) and I had to clean them all before re-establishing the workgroup and my Internet connection.

I've chosen to re-install Windows completely incl. reformatting the disks. I have clean backups of data held offline.

On two computers there's been no problem and they are running like new again. On the third, the internal CD drive has malfunctioned so I tried installing from an external drive.

This works for the first phase of the installation. When Windows Setup reboots the machine and commences the second phase, it tries to access the internal drive which doesn't work, and I can't find a way to direct it to the external drive.

I don't want to buy a new internal drive if I don't have to. Is there any way I can force the setup program to access the external drive for the entire process?

You could get complicated with a unattended install script.

OR you could boot up on a floppy, fdisk/format the drive, copy the W2K i386 folder from the 2nd drive to the first and run install [winnt] from there.

I'd fix the CD drive or borrow one from another machine.