I ended up getting the engine and transmission. Ordered the transfer case adapter, and am in the process of gathering everything to swap the output shaft of the transmission. I just need to track down a few more parts and figure out which style of output shaft I need (there was a change between 2012 and 2014).
I am planning on picking up another 4x4 crossmember and modifying that to fit the engine. I've seen at least one other person do the same. Right now the truck is running and driving, and don't want to tear it apart until I have everything ready so I will probably be taking careful measurements and will move the crossmember fore or aft a few inches to fit the engine.
Originally I was going to go with an off-the-shelf bolt-in crossmember, but after talking to a few difference companies, it was clear they only work if you lift it at least 2". I will be keeping it stock height.
An important note for anyone doing a GEN IV swap:
You only need the gas pedal (no TAC module) and OBD II port from the cab.
Unless you intend on keeping the body control module, you will need to buy a CAN bus cruise module if you want cruise control. Like this one:
paceperformance
There are other cruise control kits. The CAN bus makes it easy to setup since you only need the two CAN wires that are connected to the OBD II port. Pretty much everything is wired into the ECM (brake signal, Vehicle speed, etc...), so the module pulls almost everything from the CAN bus.
I have not yet confirmed this but this will likely be the case:
The TUTD (Tap up and tap down) transmission shifting system can be operated via the CAN bus or the wired input. By default, it runs through the body control module over the CAN bus, the TCM must be enabled to use the wired input. This will allow you to use a simple switch with a couple resistors to shift it manually.
If you are using an E38 ecm LT1swap.com has an ECM pinout diagram: pinout This also has the wires that can be removed. I will be confirming that each wires goes to the location described before removing any.
The TCM pinout is attached. Note that XCM is the transfer case control module. It is an extension of the CAN bus to transfer case. These wires aren't necessary unless you are using a newer transfer case that has a control module.
If you have a turbo350 and 205, and plan on buying the advance adapters kit for 6l80/6l90 to 205, it is longer.
Bellhousing Flange TO transfer case mounting flange length for the transmission and adapter:
This is for the figure-8 (non circular) NP205 only!
Turbo350 and adapter: 25.125"
6L80 and advance adapter: 28"
6L90 and advance adapter: 29.4"
The turbo350 to np205 adapter is 3.5"
The
6L80/90 adapter is 4.7" (according to an email from AdvanceAdapters)
I'll probably split the additional 4" of the drivetrain length between moving the engine forward and transfer case back. It's unlikely that you can move the engine far enough forward to avoid having to shorten or lengthen driveshafts.