When adding a second hd to a system is there a single mbr or 2 mbr's: one for
each hd?

When I 'fdisk wd1' it indicated that wd1 has no disklabel. 

Wd1 contains a bootable XP os, does it need labelling?
I tried to label without losing data but it did not work.
ie. copy ficticious disklabel created into /etc/disktab and use this
to add a label to the hd.

The menu that I constructed shows:

F4: NetBSD      ie. partition 3 on disk 0
F1: WinXP           partition 0 on disk 1

but I had expected: F1: NetBSD
                    F2: WinXP

Is it possible to show both drives in the one table?

-- Koz