Ok after weeks of working with winISD and Bassbox Pro 6.... Im finally stumped. I had a box build not long ago and loved the design but it was just a little to big lol so needless to say it didnt fit. For some reason no matter how I try I can't get the design that I want to work so I figured I'll let the world have a crack at it.

First: The designs that I would like to try and achieve:
This is the box that I build that was to big BIG BOXJL did a great job with what I gave them and the design was almost spot on... The only thing i would like to change from that layout is to try and have the ports firing to the rear of the box and not the front ( i remember reading somewhere that having them fire to the rear is better spl inside the car) I also love the ports being on the bottom as far as style points for me lol but ill take slot ports on the side top or bottom.

Question: With a car that always has the back seats down... the subs firing towards the trunk and pushed to the back of the trunk as far a possible. Is it better (Louder on the inside) to have my ports firing towards the rear seats?

Second: My vehicular specs:
The car is a 2007 Volkswagen Passat 2.0T
The trunk space that I can work with (for sure measurements this time lol)
These are external measurements
Max Width- 33 inches
Max Height- 16 inches
Max Depth- 36 Inches

Music that is played in the car is mostly rap but I really do listen to everything from country to classical to dub to jazz to oldies... You name it I play it, but mostly rap lol

Third: The equipment:
(1)Sony DSX-S200X
(1)JVC Arsenal KS-AR7501D
(2)JL Audio 12W3V3-4
T/S Parameters that I could find
Fs: 26.72 Hz
Qes: 0.472
Qms: 7.572
Qts: 0.444
Vas: 2.844 cu ft / 80.54 L
Xmax: 0.510 in / 13.0 mm
Efficiency: 87.15 dB SPL
Sd: 80.600 sq in / 0.0520 sq m
Re: 3.563 Ω
Znom: 4 Ω
Driver Displacement: 0.071 cu ft / 2.01 L
Question: How do you model bassbox pro or winISD to calculate for slot ports like the ones in the design and also with the specs and information given what would be the best box setup to achieve maximum SPL with low end fun for a everyday listener/driver (I ask because I might make something different in the future lol)

Fourth: Material:
3/4 (0.75) MDF wood for the sides, top, bottom, back, and ports
1 1/2 (1.5) MDF for front face and the subs will not be flush mount (front mount instead... no tools to flush mount)

Question: Is 3/4 good or should I go 1.5 MDF the whole way? Will it make any difference?

Ok everyone sorry for the wall of text... I want to thank you for sticking through it
If someone has design they can make to fit what I'm looking for that would be great and I would probably use it for sure, but I would still want to know how things are calculated and such for future reference.

Again Thanks in Advance,