Molly said:

I once tried to create a widescreen hybrid based on the RIC, but my head exploded.

The deleted scenes on the Richard Donner Cut shows some of the RIC footage in widescreen. So a print does exist somewhere. I'd love to see it. Of course, I'd love if they simply remastered it to lol.

Check out Booshman's S2 HD redux page over on fanedit.org. He took the audio and rotoscoped some footage from the RIC to give us the full scenes when Superman and Lois talk at the end after they leave the fortress of solitude. The first kiss scene outside the fortress, and the balcony goodbye scene right after. It was so nice to hear those music cues again. They work so much better than just lazily re-using the Williams score (as Thau did).