We are going to fab some headers, not too big though, we want to keep the torque. I think the camera angle makes the frame rails look really close. The standard manifold does fit between the rails, extra work on the firewall would have to be done if the stock firewall was retained. We have fitted the motor as low as we could get it because of the blower, extra clearance could be got by lifting the engine mounts.
Thanks for the help with the avatar