This starter is on a 600hp 416. The battery is relocated to the trunk. I used 2 gauge wire for the +. Hooked the negative to a bare metal spot where the supports are on the rear of the trunk.
ahh now we hit the trouble area!, the engine needs to be hooked to a negative battery cable in my experince to work good, if this is not possible at least clean the grounding spot and add a ground cable from engine to frame (thick) to replace the one suppost to be hooked from engine to battery negative