My 97 300D will not start. - no fuel.

[red5jedi]

I’ve been reading here for some great information on how the fuel injection works on this 606.912 engine but I still can’t get it going. It turns over with no problems. With the attached diagram of the fuel system I’ll list out the things I have tested.
Note: I have been running a 10 gallon WVO, 5 gallon diesel, 1 gallon RUG blend for 15k miles. Before the car didn’t start it was running great with no problems- the day temps were in the 50’s. Car has 118K miles, Albuq, NM.

1. Disconnected line 4 from lift pump – pumping fuel, seams good.
2. Disconnected line 8 for the return line – flowing.
3. Disconnected the hard lines at the injectors – No fuel.
4. Installed a fuel pressure gauge between fuel filter and shut off valve – No pressure but has fuel flow.
5. Moved gauge in-between lift pump and filter – No pressure but has flow.
6. Closed off the return line and now get 15psi on gauge.
7. Checked over pressure return valve and thought it was bad – replaced with a new one and still no change.
8. Removed all injector pipes on IP and removed the spring and other parts (names???) and they looked ok. Reinstalled and no change.
9. Removed fuel line 1 (supply from heater) and line 8 (return) and put them into a fuel bottle – this was to check if the screen in the take is clogged. No change….
10. Replaced filter – wanted to see why the return line was connected to the filter mount. The filter mount has a small hole in it that allows fuel to return back to the tank before filtration.
11. Again checked for fuel pressure between filter and shut off valve and don’t get any pressure until I crimp the fuel return line..
Any suggestions on what and how to test something I’ve missed? How is the IP controlled? I see that big black line that goes into the back of the IP then travels over so some round module that has wires connected to it. How does that work?