Ok, it is hard to see in my pictures, but here it goes.
This is the supply line. It tees into the water separator with one valve going to the diesel tank and the other coming from the veggie heat exchanger on the firewall.
In this I'm trying to get a picture of the return line. It is a metal line coming up and out at about a 45* angle on the back of the pump behind where the Bosch tag is. I cut it and have a piece of rubber line coming up that goes to a tee and some valves. One returns to the veggie tank, the other to the diesel tank. You can see the black hose and the clamps in the picture, but you can't REALLY ID location. There was just too much crap in the way and I apologize, but that should give you an idea.