C8.25 Vent?

I'm not finding a vent/hose for the C 8.25 on my '99. Am I blind or what? Looking to extend the hose for the possible water crossing but hard to do when I can't find one at all. Found the one on the D30 up front easy enough.

Thanks.

It's a hollow "bolt" that holds the brake line splitter to the axle. It runs to the inside of the rear frame rail on the drivers side.

On my 94 the vent is behind the interior trim panel behind the spare tire.