From auto to manual!

I think i'm a lucky guy 'cause my 01M trans. is working ok since now. I have heard a lot of people complaining about this transmission. my car has 76k miles and I think is time to be prepared for some major work on transmission. So I was wondering, how difficult is to switch from auto to manual. is just gearbox and pedals or is more than that. Does it worth it? Please help me!