These?:
https://www.kicker.com/comp-12-4-ohm-subwoofer
If you can fit it, I think it will work OK. My box is 7.5" at the bottom with the seat all the way back. I'd go sealed with as big of a box that you can fit. I wouldn't go ported with that sub/amp combo, plus the box size would be huge. You would also need the theile/small parameters from Kicker and run it through a modeling program to calculate volume and port tuning.
Kicker doesn't provide enough parameters to run it through a modeling program, so I wasn't able to come up with an "optimum" size. However in the owners manual, it says 1.25-3.5 cu/ft sealed.
Here's a calc that I use for box dimensions/volume:
http://www.bcae1.com/spboxnew2.htm
That's slightly too much amp for those speakers. But, it should be fine if you keep the gain set low. Wired parallel (optimum), it will see a 2 ohm load. Wired in series (8 ohm) I don't think there is enough power. Whether you run one or two comes down to how much space you want to sacrifice.
What were you thinking about for changing amps?