Steering coupler and headers

I have a 74 Duster with Headman headers and powersteering and have no clearance problems. My son has a 73 Dart and we just installed Hooker headers and the steering coupler hits the headers when turned. When the wheel is turned from right to left the corners of the coupler strick the header tube. Both cars have 318 engines and the headers are identical as far as I can tell. It there a different coupler available?