My goal.

[AceInfinity]

I believe he only has 20lb weights, even a beginner can bench, shrug and row more than 40lbs, pushups and pullups will only do so much.

There's a difference between heavy and too heavy, I am obviously aware of the fact that he shouldn't sacrifice form for weight, thanks though.

Ahh... yeah then 20lbs won't do anything barely for back exercises. You need that pulling machine, I don't remember what the name for it is though, it will work on your lats though, then for your lower back you can do reverse sit ups I believe.