With the schematic that LarrBeard provided, the battery (6 volt) voltage is applied from the starter solenoid/ (starter positive post if a starter pedal is used)to the fused link (1), as you figured to be correct. The Ignition terminal (2) goes to the negative side of the coil, in which it goes through the ignition switch. This is where the relay is turned off and on through the ignition switch. The 3rd terminal goes to the kick down switch terminal A. Then the remaining terminal (4) goes to the Solenoid terminal 4. With all this being said, the make up of the relay is very similar whether it be 6 or 12 volts. The relay that is pictured bellow from Kaiser Willys, and it is 6 volt.
https://www.kaiserwillys.com/categor...nar-suspension
If your relay does not match with what we are talking about, please include pictures of what you do have. It tends to help us realize exactly what we are talking about.