My major issue is getting the bolts on the inside of the outer clinders in. There is not enough room for my bolt heads. I think I'll use a C-clamp to flatten them there enough to get the bolts in.
I had the same problem with my Thorley headers. In fact, I've been running them without the inside bolt on the #2 cylinder for several months now. I might try your C-clamp idea. Also, I learned that carburetor studs are the same size as those bolts. So I am using them on the outside bolts holes on each end of the headers. Makes 'stabbing' them a little easier.
