Getting the DC board back in required a non-trivial amount of force to get it into position and lined up with the screw holes. It seemed to want to sit away further from it’s hole in the external case than it had to be to line up. I eventually got it in by leaving the main logic board out of it’s final position (but with the cable connected), which allowed me to get the leverage to push the DC board in so it would line up and be screwed in. Once it was in, I then positioned the main logic board and screwed it in.
I used the J000 bit (I think this is a JIS bit, not Phillips) for these screws and they seemed like a much better fit. It seems like the screws aren’t actually Phillips (ie. with the curved, cam-out corners) but are squared off.