You need to stop and take a deep breath, throwing a bunch of parts at it, isn't necessarily going to fix it, yea you could get lucky but it's costly.
Start from the beginning.
Your original most likely issue with it was contamination in the fuel, be it water, gasoline, or just plain old junk.
Or it could have been that the glow plug circuit took a dive.
Knowing those two points.
Check glow plugs, first remove the connecting wires and then OHM each one out, 2 to 8 Ohms is about right, if it infinite or 0 OHM's then you have a dead glow plug.
Then if they OHM out fine, reconnect the wires and use either a test light or a meter and check for power on Key switch Glow and on crank, should have power to the plugs on both key positions.
Next Drain all fuel, do not put any fuel back in it yet.
Remove both the fuel inlet to the Injection pump and output lines.
Bootle feed the Injection Pump from above the engine, set throttle to high, crank in short intervals to first burp air, then look for about ~ 6" fountains from all three Injection outputs, if any are really lacking then pump needs rebuilt.
If that is good then leave bottle suspended for a couple of hours, note fuel level in bottle, also note oil level, a couple hours later check level if no real change then pump is fine, if fuel level has dropped significantly then pump needs rebuilt.
Report back on what you find!
Here is some likely possible causes to why everything has spiraled out of control.
As far as run away and loss of control:
Bad replacement injectors, (non sealing injectors can cause runaway and hard starts).
Installing the fuel return fittings on backwards, (does not allow excess fuel to be bled off, thus causing over pressure and over fueling)
Fuel contamination, (wrong fuel or fuel contaminated with gasoline, even very small amount can cause odd running or over running conditions)
Damaged injection pump, (But very unlikely to cause runaway of the engine, because you never removed it (misalined linkage.)
If you are really getting fuel in the oil, there is only three paths:
Bad injection pump, (Above test will show that, but very rare).
Bad fuel lift pump, ((will test next phase) might also explain original no start condition).
Flooding injectors, (this does sound plausible considering your run away engine)
