I don’t know what “per spec” you are using but this is the way it was built.  The mercury switch prevents starting with high throttle setting,

If your solenoid has been replaced with a slightly newer version than is in Frank’s diagram; or if your motor is a slightly newer iteration than the one in Frank’s diagram, it will have two small terminals on its side instead of one. If this is what you have, connect one of the small solenoid terminals to the starting button (as the one is in Frank’s diagram), and the other small terminal goes to the wire on the Mercury switch. The Mercury switch is a position-sensitive on/off switch that is on the throttle linkage to prevent cranking if the throttle is set too high. It provides a path to ground to energize the solenoid. The Mercury switch wire sometimes meets up with the 2nd solenoid wire at a mounting screw for the round rev-limiter that is 6 or 8 inches above the Mercury switch on the side of the engine – this screw is insulated from ground and is used as a handy terminal to connect the wire from the solenoid to the Mercury switch. You do not have to use this screw to make the connection to the Mercury switch, as you can wire directly from the Mercury switch to the solenoid. Do not connect it to the center screw of the rev limiter that has a wire going up under the flywheel .
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The solenoid in Frank’s diagram has it’s energizing coil connected to the solenoid’s metal enclosure instead of to a 2nd small terminal, getting to ground through the solenoid mounting screws instead of a Mercury switch, so there is no safety high throttle starting protection.
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In the diagram below, the “Rev limiter” is referred to as a “cutout switch”. It keeps the motor from over-revving and self-destructing if you shear a pin or somehow get RPMs too high some other way.
-Dave

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Ken Smith