single mm1240dvc. enclosure

Hello. I am trying to figure out if polk has a set of specific dimensions for an eclosure for a single mm1240dvc. Which will be wired up to present a 2ohm load at the amp. And powered with (from amp specs on mfg documentation) 400w rms at 2ohm. From the amp.

I was also wondering if polk or anyone has input regarding the enclosure type and which one if applicable which would be the most appropriate type between

single reflex 4th order bandpass (sealed behind sub and front is enclosed and has vent.)

And then shape of sealed box.
regular square/rectangle.
Or. Trapezoid-ish. (Subwoofer mounting surface is only angled surface rest are all at 90 degree angles

Also. Is the 0.88 cu ft for sealed enclosure. Is that accurate or should the enclosure be a tad bigger

Vehicle: 2002 infiniti g20
Sub will be in trunk

Subwoofer: 1, 12inch polk mobile monitor model mm1240dvc

Amplifier: mb quart formula series fx1.400
(Ab class mono amplifier
200x1w rms @4ohms
400x1w rms @2ohms. )

Any info, insight etc. Is much appreciated. Thank you in advance