ok ive ha d a 351 in my car for bout a year now 85 GT i have mac LT swap hedders w/ ball style collector when i put the engine in i took it to a muff shop and had just plain dual exh w/ 2 chambers and turn downs put on it well i wanna put a X or H pipe on it now and tail pipes my problem is i never see any listed for the 351 w/ full lengths i wonder if they compensate for the width difference when making the swap hedders or are the collectors gonna be further apart any one run into this?