Axle Vent
I appreciate all of the ideas. Seems there are lots of ways to go.
I just ordered this:
Mopar Rearend Vent Bolt
I'll carefully add some weld to it, get it turned to size on a lathe, and then run a die on it to 14 t.p.i.
:thankyou:
Edit: Thinking further, maybe it can't be chucked in a lathe because of the cap. I'll see what the machinist says.