Working with multiple docuemt types

In an ASS app that I am currently working on, I have set up 4 different document types. All are of the NSDocument Class. One is intended to be specific to the app itself (i.e.: saved/opened using Data Representation/Load Data Representation handlers). The other 3 are intended to be be text files (with the text saved in different formats, i.e.: tab-delimited, space delimited, etc.).

I would like to have the open/save menus and buttons work with the Data Representation/Load Data Representation handers and use an “Export” menu item for the other 3. Is it possible to use a standard “Save” dialog for both types of handlers, such that when Save is chosen, no pop-up button displays in the dialog and when Export is chosen, a popup button with the 3 text file NSDocuments will display?

Thanks in advance,
Brad Bumgarner