Hard to say without pics / more info. Check out some of the auction results and see how your car compares condition wise. For example, this one sold twice in 2017, once for $28k at Indy and then at KC for $35k. I think member Chuck Nixon bought this one? https://www.mecum.com/lots/KD1117-298768/1967-buick-gs-convertible/ This one was high bid to $22k, but no sale. https://www.mecum.com/lots/KM0318-323373/1967-buick-gs-convertible/ This one sold for $47k https://www.mecum.com/lots/SC0518-326192/1967-buick-gs-convertible/