2 12s ported firing forward...help!

[TaurusBass1021]

I am starting my new box build for my 2 12 inch Pioneer TSW304r's within the next week or so that will be going in my 2000 Ford Taurus, and Im looking for some ideas on the box build.

First Question:

Would firing the subs/port forward be louder than having them rear-firing?

Or..

Second Question:

Would it be louder to fire the subs forward with port firing up through rear deck in between rear deck speakers?

Also I will be sealing off the cabin from the trunk completely since my back seat does not fold down. One person that also has a taurus like mine suggested to have the subs fire up with the port firing through rear deck. I just dont know which way to go with this build but I dont have money to wasye with different box builds. The trunk is pretty airtight already but no matter what I will be sealing off the cabin to try and help my spl.