Stock headers have "winking" at the runner to log weld (particularly on the drivers side # 3 & 5). I have cut doors in the manifolds on the back side for cutter access. Be cautious about not removing weld material. I have also seen winking on the passenger side header. This is free torque & improved spool.I’m running stock headers going 10.0s. I believe stock headers have been deep in the 9s. Spend your money elsewhere. Only down side is stock headers tend to crack but once you fix that you should be good. Also nothing fits like stock. So take that into consideration. I seen people complain about fit issues with ta headers, gn1 headers and even hooker headers. Also my combo is in my signature.