Yes, IF your stud will pretty much thread into the block before it starts hitting the head (once the head is on) then I would turn the "center" section of the stud down.It doesn't look THAT far off....You can measure from each side of your string to the edge of the stud (IF you have calipers) THEN measure the diameter of the string, divide that by two and then add that to each of the measurements you got from each side of the string and the difference between those two numbers should give you a "basic" idea of how much you are OFF. THEN divide that by 2 and that will give you a good starting point "Idea" of how much to take off the diameter of the stud and how much to open the hole in the head. It's NOT true machinist accuracy BUT it will get you close. THEORETICALLY, once done, you "SHOULD" be able to install your head, then leak lock and install your cut down stud. I'd wait 24hr to let your leak lock set, then torque your nut to the stud
BY they way, the leak lock looks good on your other studs!!!!