[NorCalC20LWB]

I put in a Vintage Air system, but ran into the exact problem you have. The bracket they sent you looks exactly like the first one Vintage sent me, which was for manifolds. I called them and was told there is a specific bracket for headers and they would mail one to me. Worked great, just a bit of grinding to create a little more clearance, then fit like a glove.

I'd call them back and ask if they have the correct bracket for headers, if not (which would be really odd since you're not the only one installing with headers and not manifolds) I'd try calling Vintage Air and ask if their header bracket will work with a Classic Air system.

Here's a pic of the correct VA bracket installed....