Subwoofer wiring

I have dual voice coil subwoofers .

The have direct leads from the voice coils .
So there are 2 positive and 2 negative 8 guage wires on the subwoofer .

What’s the best way to connect both leads together then to the speaker wire coming from the amp .

Do I twist them all together and tape them , do I solder them together or use some sort of butt connecter ?
 
It's going to be difficult to get a good connection with a butt conector with two 8s in one end and one in the other end.

If you strip the plastic and crimp them and then solder the connector (full and into the wires, use flux) you'll get a solid connection. Use two layers of heatshrink to insulate.