Custom Linking

I currently have a site in development and need either the services or portfolio categories to go to existing links on the the site. I did find one solution on the forum to use redirects but the content I have has been SEO optimized including the titles and URLS. I really dig this template but this seems like a bit of a deal breaker just for the fact my content has been optimized. Below is the domain all of the main navigation is where I would like to point the services/portfolio pages. Any and all help is greatly appreciated.

http://simulisplumbing.com/dev/

Bryan g