Plug-N-Play engine swap

I have a 2005 Legacy with a EJ253 (failed) engine and a TZ1B7LC transmission (love it in the snow and steep grades). With winter rapidly approaching, I need to get her back on the road.

I have spent considerable time researching for an engine that is as "plug-n-play" as possible and could find little or nothing on engine compatibilities. I only need a normally aspirated, 2.5i (170HP?) as complete as possible (being retired, I'm not looking forward to anymore than bolting on and plugging in an engine nor the expense of a turbo, diesel, etc.), either US or Japanese manufacture (we live in a "frontier" county in CA., less than 7 people per sq. mile, and therefor have no smog inspections).

My son (lives in MN.) is very adept at re-flashing the ECM and will work me through that, if necessary.

Any help for an old guy?

Your 05 EJ253 is rated at 165 hp as opposed to the 170 of the 06+. For the easiest plug n play I would find a 05 EJ253 that is running or rebuild your blown engine. The 05 EJ253 is not as common as it was only produced for early 2005's (2004 to early 2005 build dates).

Finding a complete running 06+ EJ253 will be easier just get the ECU.

There is no such thing as winter.

At least not here.

Thanks, and now for another question: I have located an 08. Is there any major chassis or configuration changes that would cause this engine not to be plug and play? I will also purchase the ECM. Would it be better for the cabling to be cut or would unplugging the harnesses be the better way to go? Anything else I should be concerned about?

You never ever want a cut harness. It's always best to unplug. Unfortunately most dumbass junkyard monkeys cut the harness, even on our subarus which have that awesome single plug deal.