Steve, this post may be too late for you, but what works on most headers on aluminum heads is to use 1" or 1-1/8" long allen setscrews and stainless hex nuts in place of header bolts. Not only are the setscrews gr-8 but if anti-siezed, they won't let the nuts freeze up. You can use reduced-hex jet-nuts for even more wrench clearance on 'difficult' header places. Good luck getting noise outa the thing this weekend!
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