I looked at a 78SC once that was a light blue, non metallic color. It had 17 inch Rufs and looked awesome. I think it was the color referred to as robins egg blue but I think the porsche name was minerva blue. I have an authenticity book that lists the colors for each year...too bad a paint chip isn't included for each.
Personally, I don't think you can beat venetian blue metallic...but I'm a little biased.
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Don
87 coupe