Ok so if you haven't seen all the headliners I have done in numerous focus's here on the sight, iv don't "quite a few"!
When doing interior work, or any work in that sense, you always want more then you need. Two yards is not enough, buy three at least and keep the left over for match work projects an or reference.
Also be sure to use the right SPRAY glue. I have always leaned towards the 3M 77 glue, usually takes a full-size can however be sure not to put it on too light. Put it on too heavy, and you will be looking at an odd crusty white mark on your ceiling.... Wonder what people might think