I am guessing you won't as drop shadows usually have several variations of the shadow color. If you are trying to do two color, white and green, there would most likely need to be some black to properly render the "shade" portions of the shadow. If you are printing on white paper, you might get by with black and green as your two colors, but make sure you are doing "no fill" and not selecting white as your fill color. If set on a white background, this will look correct, however, if set over a different color (or if you are using the white fill to "block out" portions of the green, you might have to do some serious reworking of your graphic - as your "no fill" will show the green parts you were trying to cover.
One last thoguht, if there are any options to get around using EPS, this may help you somewhat. The biggest limit is going to be in your use of duo-tone - only two colors
Hope that gets you pointed in the right direction.
