You might try lightly sanding the LED body to make it more diffuse.

P.
> >
> > I need to generate Red, Amber-ish, and Green from a single LED body (standard
> > T1.75 size).
> >
> > I am limited to a common-cathode device with two anodes to select the desired
> > color.
> >
> > The P391 from Digi-Key doesn't blend the colors well when both LEDs are turned
> > on, it's obviously a red and a green LED in the same package.
> >
> > Anybody have any experience with LEDs that _will_ work well?  Vendors?
> >
> > Thanks.
> >
> > Andy