Can someone design a box for me?

Wow, it is looking like you need 3 cubic feet net (after driver and port displacement) tuned to 39 Hz.

Bass Box pro initially recommended 2 cubic feet net tuned to 46 Hz, but I think that tuning is too high.

If you want a flatter response out of those subs, you really don't want to know what sized enclosure Bass Box pro recommends, unless you have 6.6 cubic feet to play with in your trunk! If you do want to play around with something that big, tune to 28 Hz.

If you were using them in the home, you would need about 12.6 cubic feet net tuned to 22 Hz.

Any rough idea on how big that 3 cubic ft box would be (physical dimensions wise)? I am now beginning to wonder if I can do a vented enclosure that would retain good sq without completely dominating my trunk.

Using 3/4" MDF you are looking at 30.39" x 19.35" x 12.53" assuming you use a 6" Aero port that is 12.42" long.

So would you say that it'd probably be better to keep these drivers in a sealed enclosure?

I would hit up Jowens500 on here. He has done a ton of diamond subs.

What type of vehicle?

I had a CM310 for a while, and that thing really kicked on 300 watts in 1 cu.ft. tuned @~40 hz. Sounded OK, too.

Do you just need a design, or a builder too?