ok first off, when does it make the sound? stopping? starting? turning? on your car the idler arm is not a wear item. the bushings are but not the arm. the bushings being worn will cause slop in the system. lower ball joints are a very common wear item at high miles. again those will cause slop but usually not a pop. it sounds more like a squeek. take a look at your guide rod mounts, they will cause a "pop" when worn out. you dont need a spring compressor for lowers or uppers. as blueranger said you can rent a tool from autozone called a pickle fork. it will do fine for the uppers, but if you plan to do the lowers it wont help.
the upper ball joints are not replaceable. you will need a new upper control arm.

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