Aint had mine out in years...never did figure out how to use the calibration board. I just used the moon or put the dark sunshade on and calibrated it to the sun. The more you use it the better it works!
I do however have a copy of the instructions on my webpage if that helps you at all? If you have specific questions I could dig it out and give you red-neck help.
Look ½ way down the page for the Wild instructions.
I printed this page off and taped it to the unit so I could correct meters to yards.