The pad overall dimensions are 104mm (4-3/32") x 82mm (3-7/32").
The spacing of the holes on center for the long side are 79mm (3-1/8") and on the short side 57mm (2-1/4"). Diagonals they are 97mm (3-13/16") on center. The pad is 8mm (5/16") thick. The metric measurements I've given are very accurate, the SAE ones aren't as close.