Broken exhaust manifold bolt

So I had the infamous cracked exhaust manifold so i'm in the process of swapping it out with an apn header. Everything is going great, got everything pulled out in about an hour but the stud on the back of the motor was missing (or so I thought). Turns out it was already broken inside the block and it's recessed about 1/4" of an inch. Problem is I can't get a drill to it so I can't use an easy out or drill it out. Has any dealt with this problem before or know of a solution I can try?

O also, is there a good way to clean up the valves while I have everything apart?

A cheap right angle drill adapter should do the trick. HF has them.
Or you could actually by a right angle drill.

X2. I did this with a '42 Willy's MB. After wasting a bunch of time, I got the right angle drill and the job was easy. If you are making an HF order to get the drill adapter, get some left handed bits. They will make it even easier.

Start with an 1/8" drill and wrap some duct tape around it to keep it centered in the hole.

Well I used a right angle drill bit, drilled a hole, used the largest extractor I could and the damn thing snapped. It was a matco extractor too. I shouldn't have been so lazy and just drilled out the bolt and tapped new threads. I just left it the way it was and used some high heat gasket sealant and hoped it worked. So far there isn't an exhaust leak, but if it leaks in the future it looks like im going to have to pull the head and take it to a machine shop. Thanks for help :cheers: