why do I need a "conversion box"? if its because of the crank sensor, I'm getting the computer with the engine so it shouldn't matter, right ? and I know about the crossmember and the driveshafts so thats not a big deal. I have a manual t-case and the seller said that the 2007 t-case is also a manual. but is that possible? I thought GM would have switched them all to electronic by 2007.