Interesting issue, Peter.

The difference between pop pressures is not significant. I'm wondering if the timing on one of the cylinders is off slightly, since you were making some adjustments along the way.

It remains a curiosity of what changed during the trip to cause the issue..........once the injectors are eliminated.

You didn't happen to peer down into the prechamber on #5 to confirm that the shaft and ball are still incact..........??