Thought I would share this.
The Mercury Marine / Quicksilver 143 Degree Thermostat with Gasket (the rubber ring that attaches to the top of the thermostat) part number 75692Q03 is a direct drop in replacement for the Polaris Parts.
Select the 143 Degree Thermostat Kit for V6 Outboards to see the correct model number as they have several grouped together.
I did measure them out and confirmed the dimensions.

Cross References:
Mercury-Mercruiser 75692Q03 (w/Seal, Single Pack)
Mercury-Mercruiser 75692Q2 (w/Seal, TWO Pack)
Mercury-Mercruiser 75692T3 (Replaced by 75692Q2)
Johnson, Evinrude, OMC 5005440 (w/o Seal, Stainless)
Johnson, Evinrude, OMC 334742 (Seal Only)
Sierra Marine SE-18-3543 (w/o Seal, Stainless)
Sierra Marine SE-18-1734 (Seal Only)
I am sure there are more, just too many to list.
The Mercury Marine / Quicksilver 143 Degree Thermostat with Gasket (the rubber ring that attaches to the top of the thermostat) part number 75692Q03 is a direct drop in replacement for the Polaris Parts.
Select the 143 Degree Thermostat Kit for V6 Outboards to see the correct model number as they have several grouped together.
I did measure them out and confirmed the dimensions.
Cross References:
Mercury-Mercruiser 75692Q03 (w/Seal, Single Pack)
Mercury-Mercruiser 75692Q2 (w/Seal, TWO Pack)
Mercury-Mercruiser 75692T3 (Replaced by 75692Q2)
Johnson, Evinrude, OMC 5005440 (w/o Seal, Stainless)
Johnson, Evinrude, OMC 334742 (Seal Only)
Sierra Marine SE-18-3543 (w/o Seal, Stainless)
Sierra Marine SE-18-1734 (Seal Only)
I am sure there are more, just too many to list.
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