I've done a good amount of work on Rams, mainly my own POVs lol. However, all of them have been 4th gen. But, to answer your question - if you can get the cannon as close as possible to the stock bulb so that it is pointed directly out, then I'd use a 120. If you have to mount it to the side of the housing or coming up from the bottom or top, then I'd go with a 360 so it shoots the light back onto the reflector then out.