Howdy boyos. So I spent the last hour contorting my arms into unnatural angles to get to the 6 and 8 cylinder on this AC 350. The results don't seem great, and I am hoping someone here can confirm.

It's a "YE" code 350 (9.2:1 compression ratio). These were the measurements (at 1600 feet above sea level):

1: 120
3: 120
5: 100
7: 100

2: 120
4: 120
6: 100
8: 100

In other words, the two cylinders closest to the firewall on both sides were all consistently low. I did the oil thing after the low readings and there was no change.

From high school auto-shop, I believe I'm looking at either a head gasket issue (the adjacent cylinders reading low), or a stuck exhaust valve on all the low cylinders. Is this about right?

And more importantly, does this sound like an engine that is worth salvaging? I realize there's very little data here, but that's all I really have. The seller insisted the car was a daily driver, but I didn't take the chance. I towed it home and have only rolled it around my driveway. It does start, idle, and the exhaust is clear.

I guess I'm just trying to decide how steep of a hill I have in front of me here. Thanks!