wheel spacer, and np203 question

[Dale99]

(np203 question)
My truck has an np203 installed by the previous owner. I changed the oil in it this weekend and it had a nice mix of water with it. I would like to run the vent tube into the engine bay incase of a water crossing. All I can find is that its in the top of the case(duh), and it is likely a threaded hole. Was wondering if someone has a picture of the top of one of these and could show me where it is. Thread size or any other info would be helpful as well.

(wheel spacer q)
I am having to run 1/2" worth of wheel spacers for my tire combo to clear my inner fender well. I have the gm rallys, 33X12.5. I have had problems in the past running spacers and wheels coming loose on other rides. This problem occurred on this truck. Short of replacing the wheels, anyone have better suggestions?