Is there any reason not to use hex head bolts to attach a header to the head? It's a real PITA to get those upper two bolts out. A box end or a socket won't fit because the header tube is in the way and all you can use is an open end wrench. Even with the open end wrench, it's still a pain because you can only turn the bolt about an eighth of a turn then you have to flip the wrench after each turn.
I'm thinking that using a hex head bolt instead would solve the problem, then I could use a socket with a hex head end.
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