>At least dd if=/dev/rz1c of=foo count=14, then truncating foo to 6816
>yields a file that is identical to /usr/mdec/bootblks.

On an ultrix4.2a system, root on /dev/rz3a,

	dd if=/dev/rz3c of=/tmp/foo count=14

gives a file identical to /usr/mdec/bootblks, up to EOF.
(i.e., cmp /tmp/foo /usr/mdec/bootblocks sez EOF on /usr/mdec/bootblocks)

My usr/mdec/bootblocks is 6192 bytes.  Drew's message suggests his
bootblock is 6816 bytes. I'm not sure what the reason for that
discrepancy is.