Step 1: Open up the cases and check the fit.
As you can see by the pics, I laid out everything and decided what to do with the parts I had to work with... I suggest you do the same and see what new ideas you can come up with. I started this project just to find a more interesting way to carry around my usb toys...my Altoids can was good, but I wanted something different. So, I was going to simply take out the battery and make the empty compartment into a storage case.
I decided against soldering my usb devices to extend the connectors. That's when I remembered the 4 port usb hub. You can get these at Target, etc. for under $10.