You can do it!! I smoked a pack a day for 20 years and quit 19 month ago, birth of my daughter. I would recommend slowly working out of your routine, I spent 3 months of slowing down. The hardest part was driving the car, old associations die hard. It sounds like you're mentally prepared; it's just a matter of changing your routines. I would take deep breaths and realize how much my lung capacity diminished over the years. Oh yeah, don't announce it, just ease out of it.
I still burn the occasional *** whilst drinking, which is rare for me anyway.