I got it last night. I used my borescope to take a peek of the problem bolt. Problem was that it did not line up. The borescope was awesome, I could even inspect the threads and see that they were not the issue. I remove the header and enlarged the hole in the direction that I knew from the scope. Used all thread in the problem area. I could not get nuts on it because it was so close to the exhaust tube. Put in the rest of the bolts, removed the allthread and the other bolt went in fine. I think studs would make the job much easier, but it looks like the space is so tight in a couple of locations that you wouldn't be able to get a nut and socket on. Thanks for the ideas!

If you have the tools make a "mini tap" out of the very end of the header bolt . Read that tip in car craft magazine 20 years ago and still use today .can take you from pulling hair out and kicking dogs to done deal in minutes. Also like to use the small 1/4 ratchet and socket for getting them started. Tips for next time i guess

You might want to get stainless allen head bolts when it is that tight...