Firebird Formula found, what to do with it

I recently had a relative pass away and we found a garaged 1980 Firebird Formula with 30K miles in his garage. I shipped it out to CO, changed the fuel, filters, rebuilt the carb and new wires. Radiator and grills were replaced. Other than that all original. Paint and exterior after a wash look new. I need to reattach the headliner and then there is some minor rust spots in the engine. Any recommendations on what else to do to it. Runs smooth but want to address the rust and do minor work to get the value up. Suggestions?

Highest value will be with an original car. Alter as little as possible.