Just in case anyone wanted to try scaling this box for 3" drivers here is how to do it.

First start with 32" x 24" as a full size.  ((insert long and boring explanation as to why here)) Then divide 10 by 3 and get 3.3 then divide 32 by 3.3 and get 9.6" and divide 24 by 3.3 and finally 13.5 by 3.3 Now the dimensions of the box will be 9.6"x 7.2"x 4.0'.  Don't ask why... I don't remember anyway and do not have my notes.

So now you have 9.6"x 7.2"and can lay out the plans on a 9.6"x 7.2 " rectangle of 1/4" High Density Particle Board.  Divide 9.6" into 32 segments by measuring 9.6" with a meter stick using metric measurements and dividing the distance by 32.  This will work easier if you use mm instead of cm.  So you will have thousands instead of tens.  

The result will be like this:

Lets say that 9.6" is 1340mm (it's not)
lets then say that 1340mm Divided by 32 is 15mm (It's not)
one segment = 15mm (Do the real measurements not what's posted here!)
Use the segments in place of Inches on the plans you downloaded and whalla!!   You just scaled the wo32 to a 3 inch driver from an 10 inch one.  

Now be surprised by how well a 3 inch driver can hit 30 hz  (actual results may vary according to driver Specs!!!! do not resume sexual activity while operating heavy equipement and under the influence of bass.  Bass may become addictive with prolonged use.  Consult your physician if you feel giddy and light headed after creating such a small sub woofer.  Psychotic episodes may indicate psychosis. Bass is not regualted or tested by the FDA. Side effects are usually mild and easily managed with use of real psychological medication. Feeling normal after a heavy dose of bass is not normal under any circumstances. read all directions and follow them very carefully. Seek Psychiactric help and a medical evaluation if product is ingested.)


HD

P.S. please let me know if this is wrong for any reason.