Motor Swap, now no power to starter, only selenoid and trigger wire

Did a motor swap, 3.7, on a 2011 F150. All went well until trying to start it. I have trigger wire, and power to selenoid from the battery. But have no power to the starter motor. New starter (bench tested perfectly), new heavy-duty battery (850CCA) is new. All ground wires have been cleaned and so have all battery terminals and connections. When the key is turned to start, it just chatters, which is throwing the drive gear out, but the starter is not turning the engine over. Checked for power at that connection and there is 0 volts. Fuses and relays pertaining to start circuit all good. Any ideas??