On this page of our game guide to Batman: Arkham Knight we have prepared a description which explains how to follow the weapons truck to locate Penguin's hideout. Batman must remain at a safe distance from the traced vehicle for the whole time.
Now you need to follow the van, but you cannot be seen by the enemies that are inside. Rely on using the grapnel and on gliding. Keep away from the ground and stay about 200 meters behind the car. The van should stop near a warehouse located in the northern part of the island. Scan the area (detective mode) from a safe distance and you will learn that there are six armed thugs around and two turrets.
Before you can enter Penguine's hideout, you first need to secure the area. Just like in other situation of this sort, try to stay hidden and eliminate the enemies one by one. You can sneak up from behind, use the ventilation shafts or make use of your gadgets. When securing the area, try to neutralize the turret locate at the back of the building. Approach it quickly when it will be facing the other way (there are ventilation shafts nearby). Lastly, deal with the turret near the entrance.