Integrating a WordPress Theme into a vBulletin theme?

[GetGamer.com]

I'm in the process of migrating the content area of my site over to WordPress as the CMS. As part of this process, I'm updating the design of the site, and upgrading vBulletin to the latest version.

I've already got a test site for the new design, running on a customized version of a commercial WordPress theme: http://blog.bigblueball.com

Now I need to create a vBulletin 3.8.x theme that exactly matches my new WordPress theme. I'm not trying to do a table-less forum or anything that radical, but I would like to integrate the header, sidebar and footer.

I've done something like this before on my current site (http://www.bigblueball.com/forums/) but this is going to require a little more finesse. In particular, I'll need to make big changes to the forum menus (I'd like to integrate with the CSS menus I'm using with Wordpress) and the login/registration block (which I'd like to integrate in the sidebar).

Has anyone done this before and have any advice or even a tutorial on how to do this? I'm looking for advice on the templates I'll need to modify to reposition some of those elements (like into the sidebar -- which will probably be in the footer template?).