Ron :
I worked on a building on the San Francisco Wharf, that had a large sign. The sign is larger than the current SF Planning code is allowing these days . What came of the discussion , is that if we did not change the sign, it was grandfathered in, as - is.
I think the only thing one could do, was clean, paint and replace light bulbs, ect.
Seems like you may have a similar situation.
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Nancy Harper AIA
Scottsdale AZ
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