Brothers engine/transmission kit is used when swapping in a small or big block engine and transmission combo into your classic truck. Works on 1/2-ton to 1-ton vehicles. Installs into original frame rails to allow the for the installation of any 265-454 cubic inch engine and transmission (TH350, TH400, 200R4, 4L60E, or 4L80E). Engine and transmission crossmembers are heavy wall tube construction. These mounts are high quality pieces that would be at home on the nicest truck in town, and strong enough for that street monster your planning. The crossmember ends can be bolted to the frame but, for high horsepower applications, we recommend welding the kit in place. Kit includes Engine crossmember, transmission crossmember, engine mounting pads, and transmission mounting pad. Brothers engine/transmission kit is used when swapping in a small or big block engine and transmission combo into your classic truck. Works on 1/2-ton to 1-ton vehicles. Installs into original frame rails to allow the for the installation of any 265-454 cubic inch engine and transmission (TH350, TH400, 200R4, 4L60E, or 4L80E). Engine and transmission crossmembers are heavy wall tube construction. These mounts are high quality pieces that would be at home on the nicest truck in town, and strong enough for that street monster your planning. The crossmember ends can be bolted to the frame but, for high horsepower applications, we recommend welding the kit in place. Kit includes Engine crossmember, transmission crossmember, engine mounting pads, and transmission mounting pad. Compatible with 1947-1959 Chevrolet/GMC Truck & Suburban Compatible with 1947-1959 Chevrolet/GMC Truck & Suburban