The fuel pump prime connector, sometimes called the test connector, is the green connector shown in the photo below. The prime connector was used on the assembly line to test the fuel pump and prime the engine for starting.
You can test the fuel pump by applying 12 volts to the green connector. The fuel pump will continue to run as long as the connector has 12 volts.
The photo was taken on my '88 model Reatta. Other years may have the connector in a slightly different location. The connector is sometimes tucked out of sight and you might have to dig around to find it.