Suite What is best? Upgrading from Subdreamer CMS to vB4
 

I am in the prosses of switching from Subdreamer CMS to vB4 suit.

I would like to get advice on how this is best done..

My root is Subdreamer/forums (subdreamrs index.php in domain root and a forum folder for vbulletin)

Should I make a fresh install in the root and import old content to it
Or
Upgrade in the forum dir and redirect to it?

What is best in this case?