May I suggest you look up the article by Pat Warner on his Micro-Adjustable Router Fence? The Woodworking Online article is a simplified version of Mr. Warner's design. Mr. Warner's design even includes a micrometer to accurate measure the setting of the fence.
A Pat Warner's article on a similar fence:
http://www.patwarner.com/routerfence.html
A different design appears in the Taunton Press books, such as "Working With Routers". A couple of photos of the Micro-Adjustable Router Fence are on
http://www.patwarner.com/router_table.html.
Cassie
Woodworking Online link:
http://www.woodworkingonline.com/