This BlackHeart LS/LT engine swap transmission crossmember is for 1963-1972 GM C10 trucks. It is designed specifically for use with Hooker Blackheart engine swap brackets and exhaust components to simplify your LS/LT swap. Provides bolt-in installation of 4L60E, TH350, 6L80 or 700R4 transmission and up to 3" exhaust without hanging below frame rails.