Engraving on back - Does it destroy the value?

[jlovda]

I own a Submariner 5513 that I purchased new in 1970 on my first trip to Europe right out of college. It is a domed bezel model with meters first on the dial. Within a few years after I bought it I had it engraved on the back(see attached picture). Does this kill the resale value or how much of a penalty would I get hit with?

Thanks