I read most of this thread. I have a good suggestion based on experience and inference.

Getting your hands on a spare IP would be ideal. Swap it out.

Since you don't seem to have that option, I am going to suggest that you advance the timing of the pump in a very rudimentary manner counter to what many will suggest is appropriate. The reason many of us drive these cars is because we have enough know-how to keep them running and get by with some ingenuity. Here, I think WVO has caused early wear on your pump elements causing fuel to be injected very late and at a decreased amount.

mark the position of the IP to the block with some kind of scraping tool or paint marker.

loosen the injector lines (or remove them)

loosen the IP (4 bolts total: 3 on the flange, one on the rear bottom near oil filter house)

twist the pump so that the top gets closer to the injectors. Try a small increment first like 3mm maximum. Now, when I say 3mm, this means that the mark you made on the IP should move away from the one on the block by 3mm.

tighten IP bolts

attach hard lines and bend back into shape. Do not tighten them at the injectors yet, leave them 1 turn loose from snug.

purge the lines by cranking the engine with the pedal completely depressed (awww.. sad pedal...)

Tighten lines up.

Pray. At least ten hail maries.

promise not to ridicule me if this does not work.

try again another 2-3mm in the same fashion

good luck!

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