Thanks for the reply. Amazingly, I've searched through the plugins and done several google searches and just haven't found a plugin that does this. Found several that do other menu-type things (such as showing a menu in the page, or widget/menus etc).
If I am daring to try this customization on my own, can you offer any suggestions of how to start? (I think I read that you're not accepting any custom work these days, but if you are let me know!)
For example, would it be wise to create 3 different template pages and call different menus from there?
Or, I found this bit of conidtional code that I could try but wasn't sure where to put it:
$exclude = '10,11,12';
$exclude = '1,2,3';
wp_list_pages('title_li=&depth=1&exclude=' . $exclude);
I know this is above and beyond typical theme support but I'd appreciate any nudges in the right direction!!