Sorry I don't have time to post pics, but if you check some eBay listings, you'll see that there is an extra chip on the TurboSIM - I assume to "emulate" an AT&T SIM. In order for your non-AT&T SIM to fit, you'll have to cut out a 9mm x 10mm area of your SIM. The TurboSIM and your SIM line up and make contact, and the TurboSIM acts as a bridge between your SIM and the iPhone. Sorry, but that's the best way I can explain it.
In a nutshell, the process goes like this:
1. perform the surgery (cutting out the 9 x 10 area) on both the original AT&T and your SIM
2. follow
this simple guide posted on hackint0sh. As you can see there, you install and run Applesaft on the iPhone. I added a suggestion (correction?) on that thread, too: post #50 on page 5.
The whole process took me less than an hour.
It cost me dearly, but this Christmas, I have a fully working OTB 1.1.2 iPhone!