You know, I often find that replacing a fastener every now and again can make a world of difference. As I recall, this is a place where I went to a stainless hex socket head screw, which has a smaller head and uses a much smaller wrench, which effectively gives me more room!
When you do a job, always assume that the next poor schmuck to work on it out in the weeds is going to be you, and refit accordingly. Just because the factory put it there does not mean it is the best bit for the job - heaven only knows how much stuff I toss and replace for an improvement (my brass hardware on my exhaust system bears this out, so does the silicon bronze hardware on the manifolds...)
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