Was in the process of adjusting the valve clearance. Had the valve cover off, had almost all of the valves checked and adjusted and then the worst thing happened .. over-torqued one of the adjusting screws and it broke in half - head came off and screw was still inside. DOH!

Thought, okay, this isn't so bad .. I'll just drill the screw and take it out with a screw puller. Drill bit broke off inside. DOH!

Alright, now I can't get to it at all so I took off the whole rocker arm assembly. Looked at the underside of the adjuster screw and saw that it's fatter on the bottom where it contacts the valve, so it will only come out from the bottom anyway.

I've got the screw on order from a honda dealer now (taping valve screw?). Let this be a lesson to you all .. don't over tighten screws!