Go the the power station at the top left of the map, just before the power station is a massive broadcasting tower. get to the smaller roof and wall grip the thicker of the 2 posts, keep going up until you reach the rope.
Go across the rope to a circle platform, and another rope. The next part is tricky as i have fallen off too many times from it. the will be a wall jump part but make sure you place yourself carefully otherwise you'll jump bad. The way i did it was walk to the silver part and in between the 2 rusted parts on the floor.
Once up climb the 2 ladders. after the second later turn around and you should see a rusty brown beam that you cam wall grip on, if you have trouble gettting to it just go to the fence and carefully double jump fom the fence to the bar. Now jump keep going up till you get to the top, then jump for the larry award and the achievement should pop.
Hope this helps.