LAX moved a few months ago to a legal minimum connect of 2 hours for International to Domestic inter-Terminal connections. Anything less and you run the risk of not being protected in the event of a missed flight.
My last few experiences through LAX would tend to agree with that 2 hour window. Taken close to or more than an hour to clear immigration/customs and with the lengthy waits most times in most terminals in LAX to clear security to get back into an airside area, I'd be hesitant to get a short connection.
The TSA site shows an average wait of 19 mins to clear security at T1 at LAX between 1100-1200 over the past month with a maximum time of 26 minutes recorded - must be all those Southwest pax that share T1 with US. You would only need to add a 15 minute delay to NZ getting to the gate onto one of those 20-25 minute waits to lose most of your buffer.