Stage 8 header bolts have a retainer that goes around the bolt head, then rests against the header pipe so the bolt can't back out. The retainer's held on the bolt head by an E-clip. I've been using them on my Harleys for 20 some years, and never had a pipe come loose. Contact them, and they'll tell you about a kit that has twelve 3/8-16 by 1 inch bolts. They won't work with stock headers. You need six 1 inch, and six 2 inch of that size/pitch for stockers. They can hook you up with whatever you need though. info@stage8.com
I'm with rodman, I've got the Stage8's on my GN and my fullsize Chevy. I have headers on both and haven't had a bolt come lose yet. Call them direct and they can piece any kind of set together. Here's there web site www.stage8.com.