I think it was Chuck Yeager who said it was the third problem that
killed you. We can deal with two problems at once but we can't deal
with three.

So my rule is to never fly with more than one known problem because
unforeseen problems have a way of appearing when they aren't convenient.

As for flying at night over the mountains that is definitely a problem.
The plane and engine have to be in perfect condition. The weather has
to be perfect and I have to be current, rested and alert. If those
conditions are met then I wouldn't have a problem flying a Cessna 152 at
night over the mountains and I have done it a few times.

I personally think that weather in the mountains is a much more severe
problem than darkness.

LG