07 jeep g.c ported box design check

Hello all and thanks in advance! I have a 2007 Jeep Grand Cherokee. I'm going to begin my install as soon as I get my ducks in a row designwise. Memphis Power Reference 6.5 components in front doors, and 6.5 3way coax in rear doors, both of those off a Memphis Power Reference 50x4 RMS class AB 4 channel. Also a set of 3.5 Memphis Power Reference 2ways in the dash running off the head unit itself, which is a Pioneer AVHX5500BHS. 1 12" Memphis C3 Sub, dual 2 ohm coils parallel/parallel for 1 ohm load, off a Memphis Power Reference 600x1 class D mono sub amp. I can give specifics on wiring plans if anyone wants to hear the plan. I have used the speaker box calculators here on this website, as well as the port size calcs here and at another caraudio website. I think i'm on the right track, but would like someone with more knowledge than me to double check please? I know an incorrect ported box can potentially destroy a sub, and I really dont want thet. I am including an mspaint file (a crude one sorry) with my box design drawn out, and includes my speakers specs that I have. I also downloaded winISD and though Im not 100% sure how to use it, it seems to work out well. Im going more for SQ than for SPL, and i think a box tuning of 34hz will work well. I listen to mostly rock but pull out some old school rap and dubstep occasionally. I know its not deemed "proper" to use 2 slot ports, but I would really like to for symmetry. You'll see when you view the picture. Thanks again in advance for any help you can give me!

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2007 Jeep Grand Cherokee Overland, Memphis amps and speakers, Pioneer DVD deck.

Here's the plot numbers from winISD. I really am not sure exactly what this means, but I appear to have a 10ish dB spike at the boxes tuned frequency, is this good or bad? Sorry I'm so clueless.

Driver : Memphis C312D2
Project by        : Mike
Project for       : you
--
Number of drivers : 1
Box type : Vented
Box size : 2.190 ft^3
Tuning frequency : 34.00 Hz
Vent  : 2 vent(s)
     15.79 in length for each
     1.75 x 5.00 in rectangle


Relative       
Freq        Gain        SPL
[Hz]        [dB]        [dB]
20.00        -16.82       67.88  
25.00        -7.38        77.32  
30.00        2.90        87.60  
35.00        10.78        95.48  
40.00        5.99        90.69  
45.00        3.50        88.20  
50.00        2.27        86.97  
55.00        1.57        86.27  
60.00        1.14        85.84  
65.00        0.86        85.56  
70.00        0.67        85.37  
75.00        0.53        85.23  
80.00        0.43        85.13  
85.00        0.36        85.06  
90.00        0.30        85.00  
95.00        0.26        84.96  
100.00       0.22        84.92  


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2007 Jeep Grand Cherokee Overland, Memphis amps and speakers, Pioneer DVD deck.

Well heck with it. I guess as long as I set the subsonic filter, the worst that can happen is I rebuild the box cause the ports are noisy.

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2007 Jeep Grand Cherokee Overland, Memphis amps and speakers, Pioneer DVD deck.