Use custom fields with wp_link_pages

Hello all. I have been making good use of the custom fields in pages and have found them very handy. However, I am delving in to quite a long series which will span many many pages. Having said that I need a better way to navigate those pages and was considering using the <!–nextpage–> tag. After a cup of tea I came back to my brainstorming and thought of my custom fields. I”m stuck on this one and if anyone can help direct me I would appreciate it. I would like to have the convenience of using both the custom fields and the call to wp_link_pages but I can’t seem to merge the two.

Thanks in advance