Some hydrovacs came with the filter attached directly inside the control body instead of the most often seen tube exiting.
Here's a link
to the breather that is in my COE. I swapped out the old horse hair looking crap for a more modern filter from a small yard tractor and added a rubber washer to seal it up when put back together. There are about 4 pics showing what they look like inside and out.
Most of the breathers I've seen are located on the firewall, not behind the seat.
Jeff
