Build/Install world via ssh

[Simon Griffiths]

Hello,

I tried to get an answer to this via web searches etc.  I have a freebsd 7
box that I plan on upgrading remotely via 

Make buildworld
Make buildkernel KERNCONF=xyz

Now im stuck,  I cannot get it down to single user because I only have
access via ssh.  Would it hurt to 

Make installkernel KERNCONF=xyz
Make installworld

Mergemaster etc.

Reboot

?

TIA,

Simon