The paper clips are just for probing the connector. Testing instructions are at http://boatinfo.no/lib/yamaha/manuals/1997-2003yamaha.html#/188 page 188.
For a quick check you can make the same connections with the sensor still in the engine. If you snap the throttle open and shut with the engine in neutral the meter should swing high to low.
You can slide the paper clip in from the back beside the wire but be careful not to damage the seal. For an on the engine test leave the sensor connected to the harness. For a propane torch test unplug it and take it to the work bench.
