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If there aren't enough threads to double nut and back it out which sounds like the case, then you can try to slot the end, heat the base and use a large screwdriver to back it out. Another solution is an EZ out extractor. If you have a welder available weld a nut on or cut the stripped threaded portion off, use a nut to chase the threads, double nut and remove. Might need a torch to break the locktite if used.