||added a pair of hi-flow cats which required we fabricate a new exhaust pipe between the header collectors and the center resonator. In order to use the same location as the Nissan cats, we relocated the two resonator flanges six inches rearward. Then we centered everything within a half inch or so; and re-welded the flanges.
That being said, most of the apparent offset in the pic is generated by the camera perspective. As Barry noted, the camera was not lined up with the centerline of the chassis. On a stock Z32 the Magnaflow kit locates everything dead on-center.