Ignition harness differences between early and late M54 engines?

[ClassicVolvoBMW]

I bought a 2001 330Ci which had the old M54 removed and a lower mileage newer M54 provided but yet to be installed. Both motors are labeled “30 6S 3” on the engine ID on the lower right side.
The later M54 has the newer style of coils and its ignition wire harness connector to the DME is wired differently than the DME connector on the older ignition harness. The connector is the same but in the older harness pin 4 is empty in the newer harness pins 2 and 3 are empty. The smaller secondary connector on the ignition wiring harness is a different shape also.
If I buy a later M54 DME that matches up with the newer ignition harness wiring, is that going to cause a problem with other connectors (ie, did BMW make other changes that would cause the newer DME to be incompatible with the chassis harness or any other wiring)? I assume I would have to get it coded to work with the EWS module.
Alternatively, I could buy an older style valve cover and use it, the older style coils, and the older ignition harness with the current DME. The valve cover off the old engine is not reusable. It has some damage where the underside of the valve cover melted or burned at the aft end of the exhaust camshaft.
What would be the correct name / model number for the DME to work with a later M54? Which option do you guys think is better- new valve cover with old DME, coils, and harness, or new DME to work with newer valve cover, coils, and harness?


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[BimmerBreaker]

Installing the early style valve cover and coil harness with coils and not even worrying about this at all would be my recommendation... these cars and engines litter junkyards, also obtainable very cheap on ebay

Personally I would not convert it to the MS45 (newer style) DME. I've had issues with a few of those but have never seen those same issues on the MS43 (early style M54 DME)

Some people do convert the early style to the later style coils by re-pinning the harness but I have never done so myself and can't find a straight answer on how it's done. They have a different number of pins, so not sure what all is missing between the two and never dug into the diagrams myself to find out. Heard some mumblings about a ground or resistor but not sure. Maybe they ground somewhere else or something but I just run the correct coils for the DME. The newer style coils are not "better"