MSD Coil Interface Module # MSD8870Coil Interface Module, GM Distributorless Ignition, Each Trigger Style: Crank trigger Quantity: Sold individually. MSD Coil Interface Modules MSD coil interface modules maintain maximum ignition performance. These modules go between the factory GM ignition module and coil packs. They have color coded wires that connect to the DIS wiring, are molded using Arathane polyurethane for its high dielectric strength, and connect directly to the factory