From what I understand the motor and transmission will basically be plug and play in the J8. The chassis will be fully assembled and 'rolling'. It will not have the motor/trans installed.
You buy these units from an AEV Jeep parts dealer.
The hemi may be a little different, but the diesel is suppose to be a drop in, plug in the wires, fuel lines, fill with fluids, and your done.
The J8 is still on my short list. I thought about installing the motor/trans in the nearest Walmart parking lot with a $200 autozone engine hoist....
That would make a good kick off for the project