Well, I would do this:
lib/ant/bin/ant -f setup.xml -Dinstance.port=8888
[Note: you can replace 8888 with a number that makes sense in you environment.]
In the past, you had to delete the glassfish directory and redo the 'java -jar' installation step. That doesn't appear to be necessary with build 57.
You can find other port magic properties in the setup.xml and setup-cluster.xml files.
vbk
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