I would like to add, that I believe it’s important to preserve the original theatrical print colors (or one of them) without interpretation, or subjective taste. I think once those are preserved, we can have a fair discussion about which colors are intentional, and which might be erroneous or otherwise.
I like your idea of basing it on the technicolor prints and correcting the GOUT as a template. I am eagerly awaiting your more accurate scans as I am doing the same thing and I currently have based it on Mike Verta’s samples with some corrections for the flaws he reported. I think this project can really help with the restoration of TESB. I’ve gone under the assumption (not always safe, but I like the results I see from it) that the 1993 Definitive Edition (the GOUT’s source) used the same process for all three films using interpositive prints. So I’ve applied exactly the same settings to all three films and it works very well. Following Poita’s current work on TESB, there are no prints of it that truly preserve the original colors so correcting the ANH GOUT to match the Technicolor frames and applying the results to TESB might be the best color source we have for it.