The Ulu Bernam Rest Stop ("Rehat") is a good spot to stop off on your trip along the North-south Expressway. This rest stop is on the southbound side of the expressway and cannot be accessed by northbound traffic. You are not allowed to stop on the expressway except for emergencies, and please DO NOT under any circumstances attempt to cross the highway on foot. Rehat Ulu Bernam offers the usual toilets, prayer room, fuel station and car parks, as well as a range of food options.
You will find the cache above head height. Please exercise stealth as it is almost certain there will be truck drivers resting right in front of the cache. Fortunately, they will probably be a lot more interested in their resting than in your activities! You should be able to park right beside GZ, except for busy holiday weekends (Chinese New Year and Hari Raya in particular), when you might find it difficult to even enter the rest stop! The hint should make the whole visit very easy for you. Enjoy your break and stretch your legs before continuing your drive!