Trevor, unless it's been re-cored, then there is no possible way a 74 Viper still has a solid balsa core.
And there are LOTS of Vipers still out there. Most of them have been rebuilt. As I said earlier, the only rare thing about yours is the green flake gelcoat.
Have a look at my 1980 Viper Rebirth thread in the Restorations WIP Makeovers section. My hull is 6 years younger than yours and was literally a compost hauler.
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