Okay, to start with, it's a mono amp, therefor you would want a single chamber, single port.
And the two speaker outputs are so you can run more than one positive and negative, if you need to.
They don't all have to be used. The 2 positives are the same, and the negatives are the same.
To get the wiring your looking for, wire the positives together on each sub, then the negatives on each sub.
Then your positive from the amp goes to one of the positives on each sub, and the same with the negative.
Negative from the amp to one of the negatives on each sub.
And then you should be wired to 1 ohm. Hope this helps.