I am not sure what the settings on the back of the speakers need to be set to or if I need some distribution piece to make this happen.You need a transformer to convert the output of any standard 4 or 8 ohm amplifier for use with 70.7 volt speakers.
https://www.parts-express.com/70V-200W-High-Power-Line-Matching-Transformer-300-226?quantity=1
The selector on the back of the speaker is to select power handling capabilities of 7.5W, 15W, 30W or 60W. If your amplifier rated output is 100Watts, it is safe to set all three speakers to 30Watts : 3x30W = 90W. Do not set the sum of power handling capabilities more than the amplifier rated output power!
https://geoffthegreygeek.com/understanding-distributed-speaker-systems/