2002 SE Engine Swap Questions

Hi! This might be a bit long-winded, so bear with me. Also, I got myself into this even though I'm not super mechanically inclined because I'm an idealist and I have mechanic friends (who have all told me that I'm an idiot for getting a project car without the skills to back it up, so that's already been covered.)

A couple months ago I picked up a not-running 2002 9-3 SE convertible with 133,000/ish miles for a really good price. The interior needs some cleaning but otherwise it's in pretty good shape - body is great, transmission looks to be good to go, and the top works perfectly. From the seller's description I was hoping that it would be a minor repair to get it back up and running, unfortunately that's not the case and we're in new engine territory. The original engine is the 2.0l and I'm pretty sure it's the high pressure turbo (VIN K.)

I've located a running/driving body-damaged 2001 9-3 sedan at 120,000 miles with a 2.0l engine that I can get for a song but it's the low pressure turbo variant (VIN H.) I'm feeling like this is probably my best option as I'll have spare parts on hand just in case there are any other surprises we find once we get into it.

My questions are:

1. The '01 engine should just be a drop in replacement for the '02, correct?
2. From what I'm seeing it looks like I'll for sure need to get the ECU reflashed. Should I use the ECU from the '01 or '02?
3. Would there be any other gotchas I should be aware of when swapping the engines?
4. Finally, the guys I'm trying to talk into this project are shying away from it because they think that the body has to be lifted off in order to get at the engine, but everything I can find online seems to say that the car can be lifted and the engine/transmission assembly can be dropped out the bottom. Is that correct?

Thanks in advance!