Need help! Rocker shaft bolt broke in head. Need removal advice

You really don't have many options. Remove rocker assembly and if bolt section is above surface of head maybe you can get a tool on it and try to remove. Otherwise drill a hole in remaining section of bolt, install an easy-out, and carefully back out section of broken bolt. Mike

P.S. If you have to drill out bolt, be sure to have a vacuum running to collect metal chips, and be sure to cover all surrounding areas with rags, etc., to keep contaminates out of engine.