Upgrading from 6.3 to 7.1 -- how dangerous?

[John Almberg]

I need to upgrade a live, production server from 6.3 to 7.1. I can't  
afford to have any troubles with this server. I have Absolute FreeBSD  
and a few other BSD books, and the upgrade process looks fairly  
straightforward. That's the theory...

Real world question: how scared should I be?

I've thought about setting up a dummy server, just to practice on. Is  
this a good idea? Or am I just a nervous Nellie?

-- John