Subaru misfire

I have a 97 Outback with the 2.5, and 180k miles on it. It idles rough, and shows codes for misfire on cyls 1&2. When I bought it (used, last year) the check engine light was on, so I did a semi-tune up and replaced plugs and wires. When the plugs were out I checked compression and it was 160+ in all 4 (engine was supposedly rebuilt at 120k). A vacuum guage shows normal steady reading. Timing is set properly. So… I replaced the coil, feeling it was the last possibility. Nope. What do I look/test for next? Other than the shake at idle it starts/runs well, gets 24 mpg and accelerates fine. Was told possible head gaskets, but wouldn’t that lead to low compression?