I recognize the footsteps you are about to take, did this with my own 603...

Put in new Monarks all around set up to 2000psi. More knocking on cold starts.

Odds are your timing is off after doing the injector job.

Chain stretch (delays timing) plus soft injectors (advance timing) work in harmony to balance timing and keep it near the mark. You changed the injectors, now you have a net delay. So play with the timing (advance it) to compensate for stretch. It will still smoke a bit at idle.

Now put a new chain in and set the timing "correctly" if you feel the need using drip tool, or do it by ear and your seat dyno (I do this works great).
When I put in a new chain, timing immediately was way too advanced and loud knocks, and I had to back it off.

The new chain addressed light smokey issues at idle... because now the valves are now working correctly again w.r.t. the rest of the parts in the cycle.
With or without ALDA didn't help with idle smoke. It was the chain. Car is without ALDA now, and I can make smoke on demand with the pedal, until the turbo kicks in and provides plenty of air.

I did the new glow plugs too while I was in the vicinity. Car now starts like a champ with one crank revolution. It seems using any glow is optional.. will start cold. Never did do a compression test, but it must obviously be good.

HUGE TIP: there's one bolt at the rear of the IP that needs to be slackened, in addition to the three obvious bolts at the front of the IP that you loosen before doing timing adjustments. Get at that rear bolt before you twist the IP. I didn't see it, twisted the IP, which cocked it so slightly to unseat the big O-ring at the front.. and had an oil gusher at that O-ring. The car didn't really need a new O-ring there, the old one was pliable not brittle. But many people say get a spare on hand before you try timing, in case yours cracks. Then you need to pull the pump and put the new ring on. I got the whole seal kit for the pump while it was out and did top valves too, even though none of them were leaking.

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Cheers!
Scott McPhee

1987 300D