Update (Stalin) : Still no luck. Tried LILO and GRUB, removed third drive (1gb scsi on id3) and reinstalled with the following setup:
sda1 : /boot 100mb
sda2 : /swap 400mb
sda3 : /home 1647mb
sdb1 : / 8676mb
With GRUB/LILO in MBR of sda, boot image on sdb1
Installation of 3500mb gets about half done and exits abnormally, then on boot I get 'Missing operating system'
Still swinging away at it. Maybe I'll get a lucky hit. Next attempt will be to completely fdisk again, repartition as above using DOS fdisk, re-MBR using dos fdisk as well, then re-install.

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