More breather mod questions (trans & front diff)

So I am going to be doing a breather mod for my rear diff. I will be putting a filter on the end of the tube to let pressure normalize and not suck water in through the seals. That said I can find the front axel and actuator breathers next to my battery. I believe I have found that the trans vents just above itself and with a 4 cylinder truck, I don't think it'd be too difficult to get to it. My questions are...

1. Where does the transfer case breather go?

2. Is it as imperative to tie the front diff, trans, and transfer case breathers into my new line?

 

I believe only the rear diff is the problematic one, the other ones are designed better