Is anyone here and expert on these older gems? Have a cosmetically beautiful pair here. Wood just needs a bit of oil. There is one tiny hole in one part of the grille... not noticeable. The one crossover tuning turns around and around and does not lock. I am loathe to take the grilles off. What would advice be on giving these a test run and to check the drivers etc. without trying to remove or damage the grills? I gather these are delicate from doing my research and it's likely [or not?] the drivers etc may need work from their age factor living at the coast.