Help - RPM Sensor Problems

Hey Guys - I feel like Im cursed with this car. I went to the salvage yard today and got 2 of just about everything. I figure if I dont use it now I can always have it for later and everything was 50% off. I get home and start to change the RPM Sensor and dropped the 10mm bolt into the sensor hole. I cannot see it. What have I done. Did this go down into the tranny and am I screwed. Any suggestions on what to do. - Thanks

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