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Dave,
Please consider:
1. The illuminated reticle, even a red one, would lower the contrast of the image. Red LED's have quite a high blue component. ie field wash out
2. The illuminated reticle was designed to guide on a star whilst a photograph was taken. You don't need a large apparant field to do this.
3. The other use of the illuminated reticle was for the finderscope. Most of these have an aperture of 50 - 80mm and are ~f/4. That's a cone of light 200-320mm long. The size of the field lens of a 9mm eyepiece is not necessarily 2" across, more likely in the order of 10mm. This does not require a 2" barrel size.
4. Depending upon where the focal plane is also determines the position of the reticle. In some designs this is not always accessible. Usually it falls immediately on the field side of the aspheric first surface. If you can design a reticle that will curve and be equally illuminated without flooding the field lens with background red light, good luck.
5. Having said that, I have in the past made an eyepiece that had a 60° apparant field of view with dual crosshairs. Quite easy to make really. The field lens in this case was a doublet with the first surface virtually flat. Couldn't make it illuminated though as the focal plane fell inside the chrome 1.25" barrel and I couldn't access the reticle with a light source.
BTW what are you wanting it for?
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