Cannot customize css of a single autocomplete combobox pull-down list

I have several autocomplete comboboxes on my site, some of which are using a different font. But when the list comes up, it is using the default size which can only be customized with class combobox-context-menu. jquery-ui does not add the name or id of my SELECT element to the list, so I have no way to customize just that list. I would like jquery-ui to add my name and/or id so that I can have custom css for just that list and not all others. Currently it uses something like ui-id-2. I have no way to determine this id. I'd like it to take the id of the SELECT element and add -ui-ul to it (or something like that). So for instance, if I have id="newcc" on my SELECT element, the UL element generated by jquery-ui should use id="newcc-ui-ul".