I did this a little different than most visitors. When I got to the end of the pavement there was some mud, and rather than risk a car adventure I decided to walk across the desert to the petroglyph site. This isn't hard to do, just one fence to slip under and it only took about 45min. While approaching these low hills I made the decision to just look around...not try to see it all. I've never been good at spotting petroglyphs and decided this might be my chance to succeed....a bit like a crummy fisherman (which I also am) being led blindfolded to a private trout farm...bound to have a good day.
I had Randall's GPS track loaded and hit the area away from the main parking lot. It was great to spot my first one (apparently not part of a popular grouping) and in a few more minutes I hit the jackpot...no doubt one of the main site's referred to in the description. The petroglyphs here went all the way up the north slope of the small hill and I followed them up to the top. I continued along the top heading south and didn't see any more till the last drop to the next saddle. I wondered if the next hill would also have north facing glyphs and headed up a ways but no dice.
I headed back via the main parking lot which is next to a lot of petroglyphs as well...though this area, with heavier traffic, seemed not as nice to me. There were two jeeps and a minivan in the lot - guess the mud wasn't that bad. Walked back across the desert, heading toward the water "silo"....very enjoyable....and I can always go back and find more!