If I were you, dl winISD pro from linear team.

Plug in the driver parameters in the correct order(look in help tutorial)

Pick the driver that models best in a 40hz 4th order enclosure with chamber sizes equal or smaller than the 24 x 36 WO.

As a rule I don't exclude one type of woofer from anything I do, i just choose the best one I can afford.

~side note~
Those daytons are nice, I just got a pair of the high fidelity 10s in a trade for some cabinets, lower power handling than the HO, but higher sensitivity and larger Xmax makes them my choice:
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=295-460

Yep i've had troubles finding a 10" pro audio driver up to doing the job.  Infact I havnt found one.  
Another reason for wanting to use a 12" was because someone I know was able to make me up a couple to order that have a very nice spec.

So for winisd  I calculate the front chamber by measuring the volume of the front WO chamber which i think is about 19l on the 24" version.  then set the tuning to 45hz. Do I leave the port info alone?
Then work out the best rear chamber.

cool.  tried that with an alpine type r, eminence omega pro and kappa pro and i'm not impressed with the graph on any of them.   Guess i'll just have to make the thing and see what happens.

one more quick question for the resident WO experts before I go choppin wood.

I cut the inside panels 14" as originally I was gonna fit 12's.  Since its a 24" version i'm building would it be possible to increase the sealed chamber and front chamber by leaving the panels 14" for a 10" driver,  but tapering the horn mouth down to 12"?  
Effectively would that mean that the only difference is a shorter horn. Or does this also mess up the suitable volume of the horn?

[quote author=Adrian D.  link=1145737888/15#16 date=1145805452]EDIT :
gex, jet's modded wos are similar to ported boxes. [/quote]
Yup. That's how they were modeled in WinISD. They performed great, over their replacements. Expecting bigger numbers in the future, with only power modifications.

8bit-ash, be sure to post pics of the build!

If youwant to cut it down, just cut everything to 12 inches instead of 14.

unless you want 12s with a 10" horn.  In which case, just slam em in there you can fit mot 12s in a 12 x 12 piece, since the cutouts are generally 10.5 or so.