jus wonderin cuz i don't want to get too big and have stretchmarks all over
What's your current and goal weight?
I think you'll be fine. I've seen some pretty drastic transformations of people losing more than 11 inches in waist size. Even in the worst case scenario you'll look a lot better than you do now.
maybe i'll lengthen it from 12 months instead of 9.
9 months is probably enough, especially cause it seems you definitely knew how to get lean before.
Have a gander at this thread http://tnation.tmuscle.com/free_online_forum/blog_sports_training_performance_bodybuilding_alpha/its_almost_time_for_my_surgery and maybe ask sidewalkdances or SSC if you have any questions.