Deskpro EN 6333 Restore CD/Recovery set

Hi

I have an old steam driven Compaq Deskpro EN 6333/4.3 UK which came
with an ultrawide SCSI (I use for for a tape drive and CD writer)

I am trying to restore the hard drive from the Restore CD (Compaq
Deskpro EN Series 6266, 6300, 6333, 6350, 6400 Version 1.0 339913-001)

The machine boots from the disc and then following the screen
instructions it formats the drive and partitions as original build i.e
C:2GB D:1GB E:1GB. Then it asks to reboot.
On re-booting it seems to re-boot from the hard drive and loads the
same restore program but then can't find the Restore CD and sits there
asking you to make sure the restore CD is in the drive.

Can't seem to get beyond this point!

I have a disaster recovery set (on CD) and I have managed to get as far
as installing the ASPI manager (checked the T20 tape drive and CD were
found) and run recover from the startup floppies.
However, the recovery programme only sees the T20 tape drive not the
external SCSI CD drive!

Can anybody suggest a work-around or have other ideas? TIA