I bought a late model rear brake bracket with the "hat in rotor" type e-brake and made a couple plates to weld on to the axle where the old drum brake brackets went. That gave me 1ton dual piston calipers and e-brake.
I cut mine and added Ls7 injectors and got rid of the spider injection. It's perfectly fine to cut into a harness, just make sure you seal the exposed wires when your done.