Roll cage just randomly spawns or has a set location?

[Lil Luig]

drove probably to 8 stops and every mechanic didn't have roll cage. go through trails and find all car parts but roll cage. Go to event thinking the mechanic there would sell it. Why doesn't it? I think that would be an absolute no brainer to put the required item for the quest for sale at the quest location, and just have the cost be a gate for the quest, not randomly stumbling upon the item.

[Cornballer]

It just randomly spawns at auto shops. Not Garages though. Getting stuff like rope, knives and a flashlight to help you explore in locations and find abandon cars gives you a chance of finding one. So those locations can be good secondary ways of finding a roll cage.

[MalteseFalchion]

It spawns at auto shops. While it's 'possible' to find it while exploring, auto shops are more guaranteed to have a variety of car parts. Exploration while you're already doing it is nice, but deliberately trying to find a roll cage would better off hitting as many auto shops on the map as you can is far more effective than praying for exploration luck.