How long and is it possible?

Howdy,
 
I'm a fairly skinny guy looking to build up my muscles a bit and I wanted to seek some advice. I'm nearly 18, about 6' tall and about 60kg.
 
Basically, like I said, I want to bulk up a bit. I really don't like being so skinny. I mean I understand genetics and my overall build is always going to be slim, but I know that I can be slim and solid. By no means do I want to have a 'competition body', as I've heard it called, nor do I want to be a bodybuilder - I just want to muscle up.
 
Unfortunately for me, I have a thing called pectus excavatum, which if you don't know, is where your ribcage kind of sinks in the middle because of how the cartlidge grows, which makes me look even more skrawny. I really want to do what I can to try bring my chest out. If I tense hard, or cough, or do chest dips the bones are pushed forward and it starts to look more normal and if I tense my stomach as well, it pulls the bottom of my ribs back and really improves the appearance. Of course, I can't walk around tensing up my whole life. So that's the first thing I want to work on. Second most important I'd like to build my triceps/biceps.
 
I did a couple of measurements and these are kind of my goals.
 
Upper arms - add about 3-4" circumfrance
Forearms - add about 1-2" circumfrance
Chest - bring out/fill out center of chest as well as add about 2" diameter. Also have more defined pecs/abs.
Thighs - add about 2-3" circumfrance.
 
If I could achieve that, I would be happy. I don't have any desire to be more built than that. But I'm not sure if those are even realistic goals. How long would it take to achieve something like that and what would I need to do?
 
Cheers for any help. 

The chest thing is hard to say because it's a matter of opinion instead of a number. But if you're a beginner, tall, and scrawny, I think you could accomplish those goals in a year of solid training and diet. I started about 2.5 years ago and weighed about 150lbs at 6'3, now I've been up to as high as 210, currently at a lean 201 lbs. Dramatic change can happen but the best thing is when you get addicted and don't mind putting in more years for the hell of it.

there really is no way for us to tell you how long it will take.  genetics, training, and too many other variables prevent any accurate prediction.  just keep your eyes on the goal, train hard, train smart, and you'll get there.

let's break out the shotguns we're going to town,
this quote from our weapons "this fight is more important than your life"
Hell is empty, the devils are here

6'2"
213
365 deadlift
265 bench
what a choir boy