A340 Rear Trans / Transfer Case Breather

[smokeysevin]

When I installed the 4WD A340 Trans and transfer case in my tundra I noticed that the rearmost diff breather (on top just in front of the transfer case) was missing the cap. I currently have a vacuum cap over the stem but need to get a proper breather on it before I take it to the beach this summer.

Is the stock fitting threaded or pressed in?
What size is it?
Is there a drop in replacement or do I need to plan on modifying it ?

Thanks,

Sean