2 0 0When you wake up at Mo's head to the trailer towards the left of the map. When you get there the trailer is locked and the owner, Todd, is downstairs in his basement. You need to get into the basement to retrieve Mo's welding torch. In order to do this you need to knock on the door, which brings Todd up. Here is where you can receive the achievement, simply keep talking to Todd until this unlocks after Ben offers to sell him some fine leather jackets.
0 0 0When you go see Todd (the torch user in a RV), keep talking to him until the achievement pops up: