I did this to a 96 Outback 2.5 at 105,000 miles, now at 135,000 and OK without being milled. You can not beat a shop, but in lieu of that, look real close for any surface cracks with a magnifier. Clean it up and keep track of the stuff to get all in the same positions. Use only Subaru parts that you buy now and have the parts guy print the installation latest version. Anything old will be at risk for incorrect. As you know, this was a learning process for them. Get a big guy to hold the motor while you torque. Replace the oil leaker plate behind the fly wheel disc. The parts guy knows what to give you.