The dribbles from 1,2 and 4 could just be air in the lines.
Crank for 20 seconds with all three just cracked, then tighten them up.
Give starter a few minutes to cool down.
And repeat until you get a good squirt, then tighten up and try starting again.
I would have soaked the the rings with transmission fluid while it was apart.
If they ran dry they could have gotten hot and be stuck in their grooves.
Have you tried starting it with a bit of starting fluid? (either sprayed into the intake hose?
DgD, that's exactly how a clogged exhaust would perform.
Under 'no load' conditions there is enough flow.
But under load the 'after turbo' pressure builds due to the restriction.
The exhaust not flowing stalls the turbo.
If you could measure rpm of the turbo,
you would see the rpm's rising...
The cat could be clogged.
And I have heard of the internals of mufflers coming loose and blocking flow.
When you 'stuff it' what does it rev up to?
Does it rev up quickly?
Does it loose rpm if you keep it floored?
I guess you'll see tomorrow.
If you could read boost pressure off of the manifold (drill & tap for a nipple) and you see appropriate pressure there,
then I'd say you're not getting the corresponding amount of fuel to make power.
Could you have a clogged fuel filter or fuel line or pick up??
I saw your last posting about the clacking noise you were hearing.
The other day I started my car and on top of the normal diesel engine sound there was a distinct 'clacking' noise.
It gets loader with load. Even just putting it in 'drive' makes it louder.
What did your noise turn out...