You're controlling a RC Car with Bentley, and must tail El Jefe. The car has a disguise that can be equipped with the L2 button, but this slows it down a lot. You can use turbo with the L1 button, which helps a lot since this whole mission is timed. If you drive by any guard and they catch you without a disguise with their flashlight, then you'll need to start over from that section.
Remember to always follow the arrow. For the first section, drive over the bridge and you'll see the first guard. Keep going, remembering to use your disguise. When you pass by the one guard that falls asleep by the overpass, there will be some debris ahead that you can destroy with the R1 button. Make the sharp left and then cross the bridge with another guard, making sure you don't accidentally run into him. Once you make it past this guard, the first section will be done.
The second section is pretty short, and will end when you get to the cave. Make sure you don't go too fast over the bridges, as there will be guards on the other side. There are only three guards in the way in the third, and final, section. The mission will end after a cinematic with Murray snagging a map from El Jefe.