how to build a ported box for 4 15s

so i want to build a ported box for 4 15" kicker comp cvr's in a 98 tahoe fireing up if possible  should i build 2 boxes or one big box the space i have to work with is W=45" D=36" H=21" i need help in the actuall dimensions of the port and the box or realy any advise will help im a good box builder but a better carpenter so if yall can give me dimensions i can work with that and the sound i want to create is LOUD!

kicker has dimensions for one sub ported as 5ft +port displacement

3" x 12.5" port, 22" long or...

3.0ft + port displacement

2.75" x 15.5 port, 25.75" long

or should i go with one big sealed box what would the box measure then if kicker askes for 1.8 ft each speaker...

Build sealed chambers for those subs.  Make it easier on yourself to load and install the beasts by building two separate boxes rather than one.  1.8 cu ft is MINIMUM size...don't use the minimum.  5 cu ft is maximum for each sub.  Try to get each driver chamber as close to the maximum as you have room for.  I believe if I were doing this, I would build 4 separate boxes.  A 5 cu ft box is going to be heavy.  A 20 cu ft box impossible.

Remember, sealed, not ported for this sub.  http://www.subwoofer-builder.com/freesoft.htm  Work with this program to find actual measurements.  You have close to 20 cu ft of room to work with.  Look to the left side of this page at woofer calculators, rectangular box.

say i have an idea but now that u say go with a biggger box im might be wrong the measurments i have are.............outer dimensions

                                 H=35" x D=35" x H=15" with a solid divider in the middle and two window dividers between the subs  i wish i could draw it out to show yall