Black ceramic Hooker headers

[cheford]

I was wondering if anyone here is using the new black ceramic darksider headers that Hooker are producing. I'm using a 72 C10 2wd chassie for my build with a 350sb. What I need to know is how much clearance there is from the header tube to the front cross member as I have moved my motor forward 1 inch for firewall clearance of my F100 panel body. The Flowtech headers I have are hitting the crossmember and not allowing me to bolt them on. I'm trying to prevent surgery to the cross member if possible. Thanks to all how reply.....John