I do have a .91 Magnum under the bench, it runs. I pulled it out of an old trainer and replaced it with an OS .91. Something I discovered, well, maybe I just never gave it any though? The Magnum header fits the OS and is cheaper. I didn't look but maybe the threads aren't cut in them as deep either?? If so I will buy a couple of there headers, the OS headers suck!!![:@][:@] Swallow!![&:]