So I worked on the motor all day yesterday.
Got that thread repaired with a Keensert from R&E. Got the propper inner-tierods for the steering rack (turns out early WRXs have different sized threads from newer WRXs).
Then I went as far as the timing belt & covers, intake manifold, oil breather plumbing, turbo inlet tube, wiring harness, etc. All the way up to bolting on the headers. That's when I found out the Gruppe-S headers I've got and the oil pan I put on both want to live in the same place.
The corner of that oil pan just barely interferes with the driver's side headers. I could probably just take a hammer to the headers and get the clearance I need, but I think the correct solution is to cut the corner off the oil pan and weld a plate over it. It's that or buy new headers, which I'm not doing.
So, now I need a fabricator. I can use my cutoff wheel to cut the pan myself, I just need someone to weld a square plate over the new angle. Then I can get the headers and uppipe on, then the turbo, and the motor will pretty much be ready to go back in the car.