Thanks to all who replied - the solution has been found.
Perhaps I should have titled the request "Lilo boot from slave ..." because the
issue was not having the master drive present, but we want to boot from it when
it is present! Problem was in getting boot from slave drive when it is the first
drive.
The fix is (in lilo.conf):
disk=/dev/hdb
bios=0x80
Works fine for me.
Thank you everyone
Bruce
Ward