I was there a few years ago. Very good claim. Drywallers have hit the arroyo pretty hard but I have found flake and string gold up in the flats. Loved it there

I got to the Grayback usually 2 to 3 times a month, First thing snakes, second thing bring plently of drinking water its very hot and dry. Now for the good stuff, if you go over on the other side of the arroyo in the flats area find a spot dig down once you hit about 8 to 10 inch's down do a test pan your looking for the dark reddish small gravels in your pan that will be the first layer of pay, if it has some gold keep at it you will also sometimes find a layer of concreated gravels that break up in your hand,,, dont toss that out, break it up and run it. Good luck i am heading down there tomorrow.
Best of luck and heavy pans
Tim

thanks to all for your info. will be leaving here 6/21 for the trip.