Don’t take this as gospel, just a memory of what could be a nasty rumour online about EJ conversions into the fugly series.
Measure up the width of the chassis rails to ensure they’re wide enough for the EJ22. I wouldn’t want you to be knee deep in the project only to find the engine doesn’t fit without major modification to the recipient vehicle! I recall a fella shoe-horning a DOHC turbo into one of these and had to do loads of mods to make it fit. From the convo around that, the feeling I got was that even a SOHC EJ22 isn’t an easy task to fit.
What’s the diff output stub spline count? If it’s 23, why can’t you retain the factory front shafts?
Personally, I don’t like offset track width front to rear - just check out the last land cruiser models for what I’m talking about. Yuck!
As for the 2wd rear end, it could be a case of finding a set of wheel bearings that fit the EA stub axle and the EJ 2wd hub. Hopefully the stub axle is the correct length for this sort of swap. After that it’s how to graft/mount the EJ backing plate. The other bit is finding out if the 2wd hub is separate to the drum (I believe all 2wd EJ Subarus were rear drum, but I could be wrong about this).
I hope this helps, I dare say you’ve got some research ahead of you.
Cheers
Bennie