I have an arch metal building. Same type, Pioneer out of Canada. I just started putting it up. I have been using the Butyl tape caulking. I have been having problems lining up the wholes. I am thinking it is the caulking. The caulking may not allow proper movement of the arches to align up the holes. I am also thinking, if the holes can't line up properly, it may cause the holes to get larger from using drift pins, which may cause leaking around bolt holes. I am thinking of trying some extra oil on the top arch, which might allow more movement of the arch panels to allow better alignment. Or, if that doesn't work, I guess no caulking, any ideas welcome. Thanks!