Well, it looks like I've encountered a problem.. I frequent a mustang forum and am swapping an SC engine into my mustang.. I cammed the engine and as a mustang guy I knew I could use LS6 in a 3.8 as the upgraded springs needed for a cam.. Well, after attempting to put them together and reading a post on here I see that the valves between a mustang single port and an SC are in fact different as the locks dont seat into the retainer correctly.. What am I going to have to use to use these LS6 springs and GT retainers in these SC heads? I dont want to have wasted my money on these springs and retainers..