A box design program

[blazinlow 0]

What is a good program to use that can help me put my idea on paper? I want to have a setup with two sealed drivers in the back of my blazer (15/18 still undecided).

I want to have them stacked like an 8, except I want the top one to be inverted this will be in a fiberglass box painted black with lightning airbrushing.

I just wish I had a program that would allow me to rig a detailed example of what this would look like....

Thanks