This location is a very remote, out-of-the-way place. If you plan it into a 2 or 3 day trip, you'll not only be able to enjoy the Sacramento Caves but also a variety of other places in the Owyhee high desert and canyonlands.
The recommended parking spot (see waypoint) may not give the shortest hike but maybe the easiest when considering elevation change. I strongly recommend against two ways down to the caves. Don't hike down the creek bed from upstream. You'll eventually come to stagnant pools or waterfall steps blocking your way. Also, unless you're an experienced rock climber, don't try to scale the rock cliffs surrounding the caves. Instead, find the gentle slope down to the creek bed a little ways downstream of the caves. The landmark for this spot is the lone juniper (see waypoint). From there you can easily walk up the creek bed to the caves. If you follow this recommendation you'll have a half mile hike over mostly gentle, grass-covered slopes.
Down in the gorge by the caves GPS signals are unstable and drift a lot so you'll probably need to rely on the hints. The cache is located in the rock wall opposite the middle (both in size and location) of the 3 caves. It's a regular ammo box mostly with stuff that might come in handy in a remote spot like this.
This area is remote so please take necessary precautions and use common sense. Make sure your vehicle is up to the task; the roads are rough and grueling so I recommend a truck or SUV with some clearance and 4WD. ATV's will do fine as well. I also wouldn't go out on the high desert when it's wet. The muddy conditions can be treacherous. As in any remote location have plenty of gas, food, water, and emergency supplies.
While in the area you should also try to make it to the Five Bar cache down in the Owyhee Canyon. Take the road from Sacramento Caves about 4 miles, first north and then east. At that point, when the road drops part way down in the canyon and becomes more treacherous, you can start hiking. It'll be about a 3 mile hike to Five Bar, first along the West Little Owyhee, and then along the Owyhee River.