Having to replace my header gaskets and want to replace the header bolts. Currently using the Proform Wedge Locking 3/8-16x.750. Just wondering if there are better ones to use. Prefer to replace with ones that won't rust. I have had to make specialty wrenches in the past to tighten the bolts at times as well. Do you prefer 12 point or 6 point for ease of tightening ?