Okay,
Step 1 - Raise the truck
Jack using the front centre jacking point
Support with jack stands at the two front tire changing jacking points.
Step 2 - Drain "lifetime" coolant.
Remove belly pan. Or whatever the BMW vernacular for it is
Remove engine brace plate. Disposable aluminum bolts? No blue paint, but they sure look the part.
Remove reservoir cap.
Unscrew blue plug bottom left of radiator, let dangle.
Catch a bunch of coolant in a strategically placed pan.
Remove the inlet water hose on the water pump (it's under the a/c compressor pointing to the rear). I got the clamp off with a 1/4 drive 6mm ratchet.
Try to catch some coolant with your (now safely emptied) pan.
Clean up the unbelievable mess with lots of cheap kitty litter.
Step 3 - remove electric fan assembly
Remove the two bolts on each side of the brace.
Unsnap the hood release cable from the 3(?) clamps on the brace.
Work the left side of the brace up and move to the left so that the right side clears the a/c hoses, then lift the right side and slide out to the right.
Unplug the electrical connector on the right side of the shroud.
Press in the lock on one side (you can see how the one by the plug works as it is not hidden by the rad hose like the right hand side one).
Lift each side enough to clear it out of the lock.
The "ear" on the left of the shroud folds back and into the shroud so it clears the radiator hose.
Lift/work the fan assembly out.
Step 4 - remove thermostat assembly
(This is where my BMW service manual has no documentation, so it might be hit or miss until I get there.)
Loosen the t-stat end of the water pump inlet hose and remove (6mm wrench accessed from the rear after to other unsuccessful tries from the bottom front and attacking from above.)
Release holds from the radiator to t-stat housing and remove - a little working back and forth and then they slide off.
Unplug the t-stat housing power connection and move out of the way.
That's where I am now. Really wanted the water pump and t-stat housing to be on the garage floor today, but then I messed around yesterday and most of today trying to get the service manual to spit out the procedure.
Next step, I'll remove the other hoses on the t-stat housing and then it looks like two smaller screws hold the t-stat housing to the water pump. Hopefully this will get the t-stat out of the way so I can access the upper water pump bolt.
Oh well.