specsheet for a simple ported 15 box

What's the internal volume and port size need to be??? This is the only way to build a proper box. I would highly advise against just putting a sub in a box without knowing what the sub's requirements are. 

This info needs to be retrieved from the sub mfr. then given your space constrictions, you may build a proper box around that.

Well which one of those boxes do you want to use? I would go with the every bass performer.

I can't recall how well an inverted setup works with a ported box but if does work, you must consider two things, one you no longer have to compensate for the displacement of the driver, and you must wire the subs out of phase.

When a box is built to specifications, usually the displacement or the volume that the woofer (basket and magnet assembly) is accounted for, so for your sitaution you don't need to compensate for it. i don't know whether or not the specs listed include the displacement but I doubt it, so build it to those exact numbers. 

Since the woofers are facing the opposite direction in the box you must wire them so that they "push" the right way, which will be opposite the normal way when inverting speakers. You may learn more about inverting subs her on this forum by doing a search, there are many topics on this subject. "inverting subs" 

When all subs are inverted, the polarity is reversed by switching the leads at the amplifier...or use the 180 switch on the amp.  Wire the sub coils themselves normally as shown in your wiring diagram.  Much less chance of confusion and mistakes.

Only when you have a combination of normal mount and inverted would you need to reverse wiring on the inverted subs.

so were do you intend on the ports being on this box?

and what are the port lengths and stuff like that