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If you connect the battery to the wrong side of the early type solenoids, they won't work by grounding the small terminal. You might check it with a volt ohm meter to see if there is continuity between one of the two large terminals and the small terminal. If there is continuity, the resistance level will match the energizing coil and that would be the battery terminal. If no continuity on either large terminal to the small one, then it is a power to small terminal type unit.
The original solenoids had the power connection for the relay coil internal to the unit. The one end of the coil was connected to the battery terminal inside there. The other end was connected to the terminal that was for connection to the start button switch. This way there would be no power connections that would require a fuse or circuit breaker. If the grounding wire to the push button shorted to ground, it would activate the starter but not burn up any wires. If you have a hot wire that can short to ground, it will burn a wire.
If you protect you wiring well enough, you can use a power wire type solenoid set up without too much worry.
Kerby