Additionally: things observed so far- definitely issues with the PCV hose. It was definitely collapsed. The interior of the engine is horrible despite regular oil changes at or between 5000-7500mi. I've had the vehicle since 2019. I wish that the sludge issue had materialized sooner- I wouldn't have bought the darned thing. Oh well. It's also shocking how closely the two engines compare. There have been a couple of moments where we took a look at the donor engine and at the one still in frame and gone, "Wait, did they sell us a DD on accident?" It's only when you see something like the oilcap being shifted over from centered to the side a piece that you realize that no, they did not in fact.
At any rate, feeling pretty positive about this so far. Wiring is going to be a pain in the ass, and we're planning to source an ECU from a '15-'16 to get around some of the programming, but that's where we sit. It's very fortunate that the DE has been worked on and worked over by a generation of tuners out there.