Using the locking tab as a reference, keep it facing downwards and work from left to right.
1: Earth / Ground (black on STEDI wiring harness)
2: Dashboard Light - Normally connected to the dashboard light circuit so that it is on when the dashboard light is active.
3: Relay - connection to your relay or accessories (blue on the STEDI wiring harness)
4: Power Source (+) - Connect to your source with an inline fuse (white on STEDI harness)