Sounds like injector wiring (or injectors, maybe swap those around, too?) is the only thing left, except of course grounds which I assume you verified, along with firing order. Plug wires can be hooked up all wrong and due to the design, a guy may never notice. I don't know that cranking pressure would tell you anything unless theres stuck valves. What did the plugs from those holes say? I would think comparison to healthy fuel trims might offer a hint. Connecting an analog (plain old regular) vacuum gauge would point out a manifold or valve problem.
I do know I am not fit to advise but one reply beats none.
