Hi Jason,
Thanks for the reply. This is kind of what I started doing, breaking walls & modifying thickness. I'm resigned to the reality that with a project like this, until we actually start stripping away drywall we really have no idea exactly how each little section a wall is framed &/or padded. The one area we did this with already was a half wall behind a kitchen peninsula with plumbing, and it revealed a combination of metal studs of various depths some padded out, some not.