any ideas on keeping the gullwings up

without gluing them
http://i30.photobucket.com/albums/c330/Lownslow302/Picture_02.jpg

Provide a recess in the door/roof seem to house a thin hyperdermic or sewing needle that you've hinged to the roof part. As you open the doors prop the needle up into a notch in the door. This should keep the doors up with their weight keeping the needle in place.

You could also attach cams to the doors that work against a flat spring that will force the doors open and closed.

When you're done with the model, glue it to the underside of a shelf, upside down. Gravity should help then. :loser:

Seriously though, I'm not too sure. I doubt there's a simple solution to this one, not involving springs and/or physics.

Are those doors metal? You can try making shocks like the Mercedes gullwings used.