Having difficulty installing on a Sun sparc 5

How big is your root partition ?
There is a limit of 1Gb on the size that the OBP, and therefore SILO can
see on 32 bit systems.
Try installing with a root slice of 1024Mb and a separate /usr of about
2Gb, assign a suitable swap and use the rest for /home.
This is what your fdisk layout should look like

1 1024Mb /
2 256Mb swap
3 Whole disk
4
5
6
7 2048Mb /usr
8 (the remainder) /home

If your root slice is already 1024Mb or less it could just be that SILO did
not work correctly the first time.
boot from cdrom
mount your root slice on /mnt
chroot /mnt /bin/sh
check that /etc/silo.conf looks right and that first.b and second.b are in
/boot
touch /etc/silo.conf
silo
exit
umount /mnt
sync; reboot

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