how to turn head bolt 60 degrees ???

[Jamesp]

A nice point from a geometric standpoint but it will be hard to accurately execute. That 60 degree swing needs to be made in one continuous movement because sliding friction and static friction are so different. To do this, print out two lines forming a 60 degree angle on an 8 1/2 by11 sheet of paper. Punch out the intersection point of the angle with a hole big enough to get your socket through. Put the socket on the bolt and rotate the paper so the appropriate line on the paper under the handle of the wrench. Tape the edges of the paper to the work piece so it stays fixed in position. In one movement, tighten the bolt until the handle of the wrench is over the second line. The longer the lines are, the easier this is to do accurately. Go for long lines