If you want to drill them out and there is any exposed thread on the stud, this works for me. Take a piece of 3/4" or 1" stock and drill a 3/8" diameter hole deep enough to fit over the exposed stud. Then drill the rest of the way through the stock with a 5/16" dia. bit. Clamp the piece of stock over the exposed stud and using the 5/15" hole as a guide, drill out the stud with a 5/16 bit. . The 3/8" hole will hold the stock centered over the stud and the 5/16 " bit matches the tap drill for a 3/8-16 stud, leaving nothing in the hole but the threads of the stud.
Joe D.
