Boy am I frustrated, just wasted a weekend fighting with these hooker headers and still not happy. The passenger side Headers went in easy and with about 1/2" clearance between the frame, The driver side even after beating the SH#* out of them still are laying up against the frame, tried to shift the engine over but its happy where its at. So my question to anyone interested is, What kind of gaps do you get with your headers/ engine combos, Mine is a 351W in a 69 .