GOT-TORQUE, the swap took me a long time and cost a lot. If you do it, you'll want the axles, suspension, driveshafts, and steering off of the donor truck. We used a plasma to hack the wrecked '06, it was wild. If you get all of the parts, most of the bolts are already in your frame so it really doesn't take much creativity. Almost all of the holes have to be opened up so there is work involved. Those axles are heavy too, you'll want help.
I bought the adapter kit from destroked. It is an engine adapter plate and 1/4" thick flexplate that mates the Cummins crank to the 4R100 torque converter. His kit uses the Ford 6. 0 starter which not only spins better, but also requires far less shaving and grinding.
Like factory parts. Best price, quality, and communication by far. He can make almost anything you need. He's even working on plug and play harnesses for Cummins conversions.
Bought my quad engine mounts from autoworldmt.com, but Scott of destroked.com is still the only guy who can really answer my questions. His truck is awesome, at a glance you wouldn't know it was a conversion, looks factory even with compound turbos. Definitely the best in the business i've found to deal with.
-Matt