Dead on 2 and 4

I'm thinking something in that distributor has gone awry. That's where the problem seems have have originated with a loose cap. The problem is deterministic, those two cylinders, which eliminates a carb or fuel problem unless you sucked a towel into the intake. There's no reason the other cylinders would be getting fuel and those two not. I don't think it would be a head gasket with good compression but I'm wondering if it could have let go in between those two cylinders?