I recently inherited my Uncle's bass. He told me through the years that this was a '51 precision (though I only I saw him break it out once). He played for years as a pro in the 60's and 70s. What's the best way to verify? Also did he wreck it by applying tongue oil and removing pick guard? First steps for restoration? Help appreciated. As an aside, I'm a guitar player, not a bass player, but this thing plays like butter. Remarkable.