If you were to ask me, I would say cut the drywall and get to a part of the pipe you could cut and re-fit the way you want. Its all couplings there and that makes it hard to work with. Someone already hacked that setup by using so many couplings. Good luck, I would say that should cost half as much as the other job.
See my work-Check out my album. "Git 'Er Done":D